Ignoring the bewildered faces Matt fitted a long rubber hose to the pipe sticking out from Lisa's gag. Lisa was trying not to panic but she was breathing deeply now making her rather magnificent breasts heave . Matt worked on  picking up a heavy metal weight on the end of a short chain and setting it beside Lisa with a grunt of effort. Inevitably this was locked to her collar. Finally Matt removed Lisa's shoes.

Lisa tried to remain cooly impassive but it got even harder as Matt continued 

"So as you can guess folks Lisa will soon be trapped in the water tank with only this rubber hose to keep her alive. Clearly she will be utterly dependent on the air supply and will need to keep calm and not panic. I want you all to feel that Lisa really is in the most complete bind we can imagine or arrange. So already she is restrained, exposed to you a bunch of strangers and soon putting her life into your hands. Is there anything we are missing ? " 

As Matt looked around the room for ideas Lisa couldn't believe her ears, what the hell else could they do to her ? She knew it would all be ok somehow but ….

"Well she's not really going to be in any pain as such? " Lisa looked at the guy who had spoken with daggers

"How about adding some sexual tension to mix pleasure with pain?" Lisa's gaze shot over to the blonde who had voiced this , she almost looked surprised herself that she had said it out loud and flushed bright red.

"Both fine ideas"

No. No they are not Lisa wanted to scream. But ever the professional she just fixed her calm smile around the gag.

"Whats your name ? " Matt asked the blonde.

"Ann"

"OK Ann why don't you come over and show us what you had in mind?"

"I er I mean no I couldn't er no really"

Lisa watched with the blonde's discomfort with a little satisfaction. She was a little taller than Lisa with an attractively curvy figure set of nicely by a straight grey dress that finished just above the knee. 

"Its ok. Lisa won't mind will you Lisa, do your worst"

Lisa nodded her assent weakly and Ann approached then stopped and blushed bright red once more as Matt handed her a small box . She paused a long long time and looked like she was about to run away. Then she took a long hard look at the chained beauty in front of her and seemed to come to a decision. Lisa wondered if the volunteer was as shocked as she made out or if the show was striking a chord with the blonde somewhere deep down.

After a few seconds thought Ann approached Lisa with a pair of nipple clamps, which she popped into place on Lisa with a shy and hesitant touch. Lisa couldn't help but yelp and for a second it looked like Ann might remove them but she reached into the box once more . A couple of seconds later and to the disbelief of Lisa and the audience a small egg type vibrator was nestling deep inside Lisa , its wire trailing away from her hips to the air hose.

The next couple of minutes were a bit of a blur for Lisa . Matt and the porters lifted her carefully and by standing on a table tipped her head first into the tank. Lisa was grateful the gag thing stopped her from gasping, as the water was cold and being upside down was a nasty shock too. The weight at her neck sunk to the bottom its short chain keeping her head just a few inches off the base of the tank.

Matt carefully checked the air hose so it ran up her back and up to her ankles. He had the porters pass him a lid for the tank which he fitted once the air hose ( and vibrator lead ) had been passed through a small hole. A short chain from Lisa's ankles was hooked to the inside of the lid holding her straight upside down in her watery prison.

Lisa was doing her best not to hyperventilate . The water wasn't freezing but was still a shock and her upside down view through the tank was tinged with a dull green. The tug on her neck from the weight as body wanted to float served to tighten her collar chain making breathing a little harder.The supply of air as she sucked on the gag was surprisingly meagre, which was more than a little scary. Her nipples were still throbbing. And despite it all she felt a deep dark thrill as the audience watched her naked wriggles through the glass. Lisa knew that ultimately Matt wouldn't let any actual harm come to her and she had trusted him with her life on many many occasions.
Matt meanwhile was continuing as if trapping a girl in a water tank was an every day occurrence . 

"So next we need to make sure there is no cheating, and you are all confident Lisa is really trapped. Ann if you could help again please? "

Ann moved closer hesitantly , as if she was starting to wonder what she had got herself into.

"Can you confirm these are all new locks , each still sealed in their packets?" Matt asked as he handed Ann a box of maybe 20 padlocks.

"They are"

"Great if you could pick 4 at random and use them to lock down the corners of the lid here please. Hang on to both keys from each lock please."

Lisa watched as Ann stood on a chair to lock each corner of the lid down. She had no way of getting out anyway so the locks seemed pretty superfluous to her but as no sound really got through to her bar the blood pumping in her ears  she wasn't sure if there was some deeper meaning.

"OK Ann now you have all the keys, and I want you to make sure that no one, not even you and especially not me can cheat and get at them. Any ideas ? "

Ann looked nervous and looked around the room as if pleading for help. 

Matt chuckled 

"Well while Ann solves that little issue I will just finish up here and explain the how Lisa here will help with team building"

Matt climbed up onto a chair himself and shook the lid hard to demonstrate it wasn't going anywhere. Then as he fiddled with a small black box up there he continued to explain.

" I am sure you can all agree Lisa is totally reliant on outside help now. Anything happens to her air supply and there is nothing she can do"

As if to demonstrate Matt pinched the rubber tube for a few seconds. Lisa could not hear a thing but her reaction was immediate, she began thrashing and shaking as best she could in her bonds , a wild stream of bubbles escaping from her nose. It was clear to all those watching she was in real distress and there was a communal sigh of relief when Matt let go of the tube and Lisa began to calm a little .

Lisa sucked wildly as the airflow was restored, it shutting off was genuinely terrifying. She had lost her normal control and had struggled madly as the tube failed to offer the trickle of air she was getting used to and even though she knew that all she was doing was using the precious air in her lungs faster she couldn't regain that inner calm. However much she tried to remember that Matt would be using his magic to keep her safe the need for air was such a deep written instinct it was hard not to forget she had a magical safety net. As the burn in her lungs reduced she did find herself wondering if the customers had enjoyed the show the thrashing and wriggling would have created.

"So Ann did you come up with an idea for stopping the keys from being tampered with?" 

"I think so yes ."

"OK Lets see it" 

Lisa watched helplessly as the blond took a fed ex envelope from what looked like a member of the hotel staff, dropped the keys she had been holding into it, scibbled an address on it and sealed it giving it back to the staff member who took it away.

"I have posted it back to myself at the office" Ann explained to the audience, smiling at Matts approval 

"Ok thats a little more secure than I planned but that works Matt chuckled. "So now to the crux of the challenge."

Lisa watched helplessly as Matt fiddled with a small black box on the table beside her, calm again but desperate to know what the hell was going on .

"How long do you think someone needs air after holding their breath ? 5 seconds ? 10 ? 30 ? Ok so shall we say 10 seconds ? " Matt took the average from the called out suggestions and fiddled some more with the box

" So this little gizmo controls Lisa's air". It makes sure she's fed some fresh air and clears what she breathes out.However there is a catch".  The room fell utterly silent. " Its default setting is off"  As he made a final adjustment it was immediately apparent that Lisa's air had once again been shut off from her struggles in the tank. " Pressing this button turns her air on, for the 10 seconds you all voted for ....." To Lisa's obvious relief the air started to flow again as soon as matt pressed a large red button. "And then of course ... after 10 seconds .... not so much with the air."

Lisa was managing to panic less as she started to realise the full nature of her dilemma. She groaned loudly around her gag as the penny sunk in about just what the team challenge was going to entail. As the air died this time she tried to maintain her control and preserve the air in her lungs. 

"Now to add a final twist to the fun, we need to remember Ann here and her contribution". Matt made on last adjustment to the little box which provoked a rather different wriggle from Lisa.

"All the time the air is in the off position the little vibrator the lovely Ann here added to Lisa's torment is on" Matt paused to let this news sink in, pressing the button after a glance at his watch. 

For her part Lisa could have cried out with shock as the vibe trapped deep inside her jumped into action. Unable to hear what was going on it took a couple of cycles for her to understand the  way things had been set up. She wanted to scream in frustration. The vibe was setting off feelings insider her totally at odds with her situation. Once again she was on show, a helpless plaything and once again it was turning her on. 

"So you see you have to choose between Lisa's breathing and her pleasure and frustration. But either way remember you have to chose. I will not touch the control any more. Between you its your job to keep her alive. How much she breathes and how long she gets that tingle deep inside is up to you. But be very clear, this IS NOT a trick. If as a collective you forget to press that button for a few mins ......"

Lisa watched Matt walk to the far end of the room as a small cluster of people formed around the box that held currently controlled her existence. She soon realised they were experimenting , as at first they were pretty much pressing the button as soon as the air stopped but gradually played around letting her wait longer and longer between gasps.

"Now I am sure this seems like a pretty easy challenge, right? There's like 30 of you guys and girls and its hard to forget the gorgeous naked brunette in the tank in the corner right ?  We will see, is all I am saying".

Time passed slowly for Lisa, broken down into a series of 10 second gasps and then interminable waits for air. It seemed the gaps were getting longer but she felt she was getting better at filling her lungs. The longer the wait the longer the interminable vibe was left running though and she found that despite the darkly guilty arousal the torture was causing her the vibe was never gonna be running long enough to let her get off properly. To Lisa's astonishment a meal was served , with what seemed to be plentiful wine. She found less and less people hovering around her and the button and soon it seemed they had organised some sort of rota to make sure it was pressed every couple of minutes or so. This was as long as she felt she could manage without air and she couldn't help but struggle as she felt the burn and bursting feeling in her chest grow. She soon added annoyance to the list. She was hung in a tank buck naked and as far as they knew on the edge of survival for their entertainment and yet they were more interested in a buffet and some free wine!

Matt took a sip of wine and noticed the blonde volunteer was slightly apart from her workmates, looking at Lisa more than any one else in the room Lisa did look magnificent he thought, the tight chains emphasising her voluptuous curves as she writhed in the tank. Whilst it was certainly a sight to savour he suspected Ann's interest was a little more deep rooted as he saw Ann bite a her lip a little bit before pulling her gaze back to the table she was at.

Lisa guessed an hour or more had passed before Matt took the floor once more this time at the far end of the room. By now it seemed to Lisa she had already become a chore, with people seeming to be "on duty " for a few minutes before handing over to another audience member and returning to the drinks. She watched Matt carefully, wishing she could lip read and wondering what he could possibly be saying. 

"So I hope you all enjoyed the refreshments, and well done for keeping Lisa with us. Now I was going to demonstrate another example of a display of trust, but Lisa is a bit more locked up than I thought... " Matt glanced to Ann...." as her keys wont be back till tomorrow it seems. I do however have a solution. Perhaps we can persuade Ann to help out ?"

Ann immediately tried to sink down in her chair shaking her head and blushing, her mind racing as her colleagues cheered and yelled encouragement. The faces round her clearly expected her to say no. Ann found her mind racing, common sense fighting with the thrill of what had happened to Lisa, for a desire she didn't like to admit to herself.  Lisa for her part had no idea what on earth was going on but there was one immediate impact, the fuss had been a distraction and she got a sheepish smile by way of an apology from the middle aged woman who had apparently forgotten to press the button. Lisa gasped in relief although she was a little horrified to discover that the extra time with the vibe and the panic had got her a little closer ...

"Ann what do you think ? Are you feeling brave ? Adventurous? "

Feeling all the eyes in the room burning into her, Ann decided that sometimes in life you just had to...

"Ok"  The cheers were deafening.

"So Ann first thing we need to do is sort you out with a costume. If you go through there you will find something that should fit ..."

Lisa watched Ann vanish behind a side door as Matt started to get ready what was clearly going to be another trick, more worryingly for Lisa this meant  another distraction for her minders, who had already proved to be worryingly easy to divert. Lisa was pretty sure that it wouldn't be long before Ann too was in to something she probably couldn't imagine. As she watched from her bizarre viewpoint Matt readied a large platform at the far end of the room. On it was a big wheel held vertically with a few straps visible. Lisa was pretty sure she knew what that was for ...

Lisa's suspicions  were confirmed when Ann's head appeared around the door a few minutes later.

"Ready Ann?"

" I . Er. I cant come out wearing this !"

"Sure you can, big hand for Ann everybody."

Ann blushed some more and kind of sided out from behind the door to whoops and whistles from her colleagues. Lisa almost choked on her valuable air supply as Ann finally emerged. She was wearing the very briefest of bikinis in bright red, and was blushing enough that her face almost matched ... Even from her tank Lisa could see Ann freeze a little as she saw the contraption Matt was leading her towards. 

Lisa's admiration of Ann's long legs and barely concealed curves was cut short as she began to realise Ann's appearance was causing enough of a stir for her to be forgotten for a minute or two. She had become oddly conditioned to a couple of minutes of no air but this was getting serious. She began to thrash wildly hoping to bang the sides of her glass walls to attract some attention but she was held too tightly by the weight. When the button press finally did come there was no sheepish look through the glass and slightly murky water or look of panic, just a lunge backward before the guys attention was straight back to Ann. 

"Ann if you would like to step up and back here " Matt smoothly directed Ann to two small pegs on the wheel. Ann complied starting to think she recognised what might be happening. In moments Matt had wrapped a thick leather strap around each ankle pinning them to the board at about shoulder width apart. 

"OK ? Matt asked. Ann didn't make a sound so Matt carried on and in no time at all Ann's wrists were strapped to the board above and to the side of her head stretching her out uncomfortably. Ann was more worried she might escape from the tiny bikini protecting her modesty than the discomfort for now, still trying to think just exactly how she had wound up in such a mess.

"So Ann the final question remains, blindfold or no blindfold ? However as you had a say in Lisa's predicament perhaps we should allow her to get involved with yours" As Matt spoke he smiled at the slightly guilty button press he witnessed as he looked across to Lisa. She gulped the air and watched Matt hold up what was clearly a blindfold then looking right at her did a thumbs up and then a thumbs down. Guessing the meaning right away Lisa shook her head no and Matt just nodded and let the blindfold fall.

"No it is then, you get the full experience Ann. By the way folks ravishing as Ann looks and dramatic as this is about to become please don't forget about poor Lisa.."

Without any further chat Matt reached up and pulled down hard on the rim of the wooden wheel which began a steady spin.

Ann gasped , she had never experienced anything like it, She was being rotated just enough to make everything a blur. To avoid feeling any more dizzy she tried to lock on an object and so found herself staring hard at the bound brunette in her tank across the room as she was spun in front of her colleagues. So she did not really register Matt picking up a box of knives, banging a few together then taking aim from about 20 feet in front of her.

When the first knife flashed away from Matt's hand towards the slowly spinning blond Lisa had to remember to breathe. Not knowing when the next air would be arriving she couldn't afford to waste a drop. Ann was so intent on not getting dizzy the thud of the knife made her scream. She didn't see it coming but felt it hit the wood by her left side. In quick succession four more blades followed. Ann felt the first on her right hand side , a second by her left knee, the third by her right knee and terrifyingly the fourth  landed high enough up between her bare legs that she could feel the air move as it impacted.

Matt used a hand to slow the wheel and turned Ann till she was back the right way up.

"Now I don't plan to ask Ann if shes ok... but , you guys would you like to come up and rescue the knives and check they are real and there is no tricks in them or the wheel. Ann held still as her colleagues moved in and pulled the knives from alongside her. She did gasp when the guy from Marketing pushed his hand on her bikini bottom as he removed the blade from between her legs She had done it and she found the thrill off being the centre of attention , the admiring glances worringly intoxicating. Before Ann had a chance to complain about wandering hands Matt set the wheel spinning once more stifling any protests. Leaving Ann spinning he turned to the small audience.

"I guess you think this is a bit too easy, and that Ann is in no real danger ?"

Still strapped tightly to the lazily spinning wheel Ann could not believe her ears. She was in no doubt the knives were real and it sure felt like she was in danger to her. She glanced down to check that she hadn't yet popped out of her skimpy costume She was just thinking that at least she had been given marginally more to wear than poor Lisa, whose predicament she had to admit looked even more terrifying than her own when she realised her view of the trapped blonde was sliding sideways. It took her a split second to understand what was happening. The podium her wheel was mounted on was now revolving too like a record deck, while the wheel itself maintained its spin. She swallowed hard, hoping she wasn't going to feel sick. 

Lisa sucked heavily on some precious air and watched the show at the other end of the room unfold with interest. She could only imagine how Matt's poor victim must be feeling. Almost resigned now to her watery prison Lisa found she could found enjoy the show although the gaps between air were getting longer again and the vibe was driving her crazy in between which just added to her need for air. 

Ann couldn't help but shriek again when the next knife landed. It was hard to see them coming with her new double rotation but there was no way she could miss the loud thud as it landed somewhere near her left thigh. She caught Matt say something about getting closer and then there was another thud. This one so close to the right side of her chest it felt like it pinched her skin as it landed. As she turned nearer to upside down a piece of cloth fluttering in her field of vision made her aware it had caught something else, her bikini.

"Hey!"

Another thud and next knife found its mark by Ann's left boob and the bikini top was hanging uselessly around her neck, which generated much applause and approval from her onlooking colleagues. Matt's next knife crunched home tight by Ann's left air. It managed to cut the string to her top too, and the bikini top slid uselessly to the floor as she continued to rotate in two axis.

Once again Matt stopped Ann's motion this time leaving her upside down but facing the enthralled audience. 

"One last spin of the wheel for Ann I think, and this one gets real interesting i think ...."

With no further explanation he reached into the box containing his blades and to Ann's total bewilderment grabbed an apple. Before she could register what was happening Matt pinched her nose playfully and in a smooth motion pushed the apple into Ann's wide open mouth from where she found she could not dislodge it however hard she tried.

"Just in case she doesn't like the next bit" Matt added with a smile.

Lisa certainly wasn't enjoying it. The removal of Anns top and exposing of her fine breasts had been impressive but had also meant that she was well over due for a breath of air. No degree of thrashing and wriggling seemed to attract the attention of any onlookers all of whom seemed mesmerised  by Ann's unfolding fate not to mention her involuntary strip tease. Her little friend inside her was still buzzing away which really didn't help. Finally just when she was certain she would black out someone hit the button and she filled her lungs in relief.

The rest of the room were oblivious to Lisa's struggle, and watched events unfold for Ann. Matt grabbed a handful of the spiteful looking blades and began to loose them off at Ann as she rotated in front of him. Ann winced visibly as the first impacted dead centre of the top of her head, seemingly so close it must have clipped her. The next two blades flashed from his hand to settle either side of Ann's slender neck. Two more found the space tightly under her armpits and the next two bracketed her waist.

Ann was breathing heavily, trying not to move a muscle. She could feel each blade skid in along side her now and the margin was scaring her. As she rotated once  more to face the room she couldn't help but spare a thought for the poor girl in the water tank. Four more knives found their spot on this rotation, glancing by her thighs and calves as they thudded home. For a few seconds the wall at the back of the room rotated in front of her then Matt slid into view once more. Ann almost choked on the wretched apple as she saw that this time Matt was hefting an axe. She saw the lethal looking projectile topple through the air towards her then it slammed into the wood of the wheel landing tightly between her legs. Another flash caught her eye and this one seemed to be aimed right at her face. She tried to scream but was stopped short by a feeling that the apple had got bigger in her mouth and then the handle of a knife was wobbling in her field of view. The final knife it seemed had hit the apple straight on. Although she couldn't feel any pain she was aware of the point at the back of her throat.

Matt took a bow and then stopped Ann's platform leaving her facing the small audience and the right way up. 

"Ladies and Gentleman, huge hand of applause for Ann".

Ann smiled weakly as Matt pulled out the knifes and axe finally pulling out the apple and knife from her mouth. A few seconds later and the straps holding her to the wheel were freed and Ann dashed to the side room one arm over her chest in a belated attempt to preserve her modesty. She closed the door with a slam and leaned heavily against it, pumping with adrenaline. She still wasn't sure if she had hated the whole thing or ... 

The small crowd returned to their drinks and observing Lisa's struggles . A few seconds later Ann poked her head round the door and said probably louder than she meant to "er Hi. Hello. My clothes have gone"

Matt looked back and did a double take.

"Ah that's really not part of the plan. Maybe the cleaners took them? "

"Well I cant go anywhere like this .." Ann nodded down to the door she was sheltering behind

"I don't know what to say. Well I do have the costume Lisa was going to finish the evening in but I wasn't going to do the last little stunt as you did a much better job on making the keys safe than I had expected".

"I, I don't know"

"Thinking about it someone is gonna have to look after Lisa till morning when those keys come back and that may as well be you". Anns colleagues nodded enthusiastically at the thought of avoiding an all nighter as much as anything else. "Seems fair ".

Part of Ann was too horrified to even contemplate going out there again, but the little voice in the back of her head wouldnt go away. And she found an odd power in the admiring looks. Bowing to what seemed the inevitable Ann nodded. Matt went to the corner and rescued a small holdall and returned to the floor in front of the now empty wheel.

"Come on over ..."

 Ann took a deep breath and padded back smiling more confidently now, one arm still hooked over her chest.  

"Don't worry, I won't do the final stunt, I really needed Lisa for that"   Matt nodded to the far side of the room " but we will pop you in the , er outfit. Do you want to wear all of it or the bare essentials ? "

Without any thought whatsoever Ann heard the phrase bare essentials and blurted out "All of it!" 

"OK "

Matt's smile made Ann think immediately that she had made a bad choice. He rummaged in the bag beside them and dragged out a clump of black leather and straps. Ann paled as she began to recognise it as Matt unfolded the mass.

"So this evening has been about team building and trust. You have seen Lisa display the ultimate trust in us all by making her very life dependent on us all. Ann too has trusted that I knew what I was doing and has also lived to tell the tale ."

Matt help up what was clearly a straitjacket and beckoned Ann closer. He stood her back to the audience and lifted it up and after a long pause she began to thread her arms into the unfamiliar device. With Matt's help she was able to wriggle each hand into the tightly fitting soft black leather. Matt guided Ann into a twirl her bare chest now hidden by the straitjacket. Once she was facing away from her colleagues once more Matt quickly tightened the heavy leather straps at the back of the device pulling them as hard as he could , enough to knock the air out of Ann then buckling them in place. The final strap around Ann's neck was eye wateringly tight too.

Matt once again encouraged Ann into a twirl . "Doesnt she look great ? " And she did. The thin soft leather was quite unlike the baggy canvas of the fake jackets used in escape acts and clung to every curve of Ann's figure.

Matt turned Ann away again and quickly tugged at the fine strings securing her bikini bottom. Ann yelped immediately but Matt reached deftly between her legs pulling two more straps through which soon were cutting into the very tops of Ann's thighs before being fastened to the back of the jacket's waist. Ann could only hope the front of the straps preserved a little of her remaining modesty while Matt reached round and wrapped her leather encased arms around her waist , using a knee in her back to pull them as tight as possible before they too were buckled  into place. A final strap fitted over all the buckles down the back of the strange garment and was secured at the back of Ann's neck with a padlock, preventing any access to the fastenings.

"How does that feel Ann ?"

Ann turned around sheepishly unsure of what was covered at the front of the jacket.

"Tight"

"Good that's the idea, nearly done" 

Matt grabbed another bundle of straps and the like and once more set about Ann. In no time she found her head surrounded in leather straps securing a bright red ball gag.The finishing touch was a long leather strap that hung like a lead from the collar of the straitjacket.

"Ok folks I think we have Ann fairly snug. I need a drink so please come over and say hi to Ann and check shes locked in with no tricks or hidden space"

Ann watched as her colleagues closed in. Her eyes blazed with embarrassment. And yet as she answered their questions with nods and shakes she felt an intense thrill she didn't want to try to explain.

Finally Matt led Ann to stand in front of Lisa's tank, facing her. Lisa looked on puzzled as Matt left Ann stood looking blankly at the table where the button rested, then she realised the poor lass was wondering how best to press it in her bondage.

"Ladies and gentlemen, the keys will be hear in a few hours but for now, good night"