She doesn't know!

"Huh. I must have put it on before I went to pee. Man, I really need to be more careful - who knows what I'll forget next!"

As she placed her shoes and socks in the locker, somehow blissfully unaware that the rest of her clothes were not present and accounted for, she hoped fervently that the cool water of the pool would help wake her up a little. She was always like this when she missed out on sleep!

The key to her locker was attached to a wrist band, which she promptly slipped over her hand. Wearing nothing but this and a smile, she stepped bare footed, bare breasted and bare arsed out into the pool area through a double set of doors designed to shield the locker room's modesty.

Thankfully for her, this area, too, was deserted. She stepped across the blue criss-cross mats left on the floor to provide grip and dipped her toe into the water.

"Damn. It's warm."

So much for it waking her up. Taking a deep breath, she thrust her arms forward, bent at the knees and dove into the pool. She felt faintly disgusted as she swam beneath the surface. The water was murky and foggy, like the filter hadn't worked or something. She could barely see a few feet in front of her. She turned back towards the side of the pool, and broke to the surface close to the wall. She kicked her legs so that she swam forward, and folded her arms on the side. Unable to resist, she rested her head on her arms and closed her eyes. Just for a minute...

She awoke with a jolt as a beach ball bounced off her bonce. She looked up with surprise to see Malcolm, the senior swimming instructor, grinning down at her.

"Morning sleepyhead." he said.

"Hey Mal. Listen, what's up with this water?"

"Why, what's wrong?"

"It's filthy. I can barely see more than a foot or so."

Malcolm frowned. "Damn. The filter must have broken. Again. Listen, can you take the first class today, while I go speak with the owner about this?"

"Yeah sure. What's the first class?"

"Oh, just a couple of pensioners, about six or seven of them. They're supposed to be learning how to swim underwater. Typical, huh?"

Jenna couldn't help but laugh. Malcolm was only a few years older than her, yet already he'd adopted a world weary, cynical approach to most things.

"I'll be back in time for the afternoon class." he promised as he retreated into the men's lockeroom.

As she waited for the old folk to arrive and get dressed, Jenna busied herself swimming laps. Her favourite way of swimming was the breast stroke; ever since she'd developed, she'd found that they made excellent flotation devices. It made the stroke so easy it was almost like she was flying.

The peace wasn't to last. Before long the air was filled with the sound of chatty pensioners - a mixture of old men and women - as they made their way into the pool area. They began to descend the steps into the shallow end of the pool, although some of them looked a bit precarious in their movement.

"Oh here," Jenna said "Let me help."

Jenna swam over to the shallow end and stood up in the water. At this depth it reached just above her hips. A few of the pensioners with better eyesight stopped talking at the audacious sight of Jenna's bare breasts, although quite a few were still blindly ignorant of the situation. Jenna ascended the first two steps, dropping the water level below her hips to reveal her crotch, as she graciously helped the elderly into the water.

"Okay. Nice and easy now." she said soothingly.

The looks of surprise and amusement from some of the old folks was a bit unnerving, but she figured they were smiling at their comrades who were less mobile than themselves.

Once everyone was in the pool, Jenna addressed the group. "Today we're going to be swimming underwater. Now I'm going to start handing out goggles, but we need to go over some safety rules first. Are there any questions before we begin?"

One of the men thrust his hand in the air.

"Yes?" Jenna asked.

"Excuse me, ma'am, but I was just wondering..."