Just off Braddock Road lies Atlantis. Its ruined pillars stand tilted in sandbars. Bright tropical fish, dolphins and even a pair of killer whales play near one of the sunken city's temples. And in the middle of it all stands Tim Grant.

He dabs a little red on one of the fish fins. Then some orange. Then he takes a step back and looks over what he has brought to this wall: a remarkable transformation.

The Wakefield Recreation Center's indoor swimming pool area was one of the center's dreariest rooms. It was dark. It was depressing. Part of the problem was the wall above one end of the pool. It was covered with gray cinder blocks that gave off the ambiance of a prison.

So when the Fairfax County center recently got ready to close the pool for maintenance, the managers looked into having someone paint a mural on the ugly wall. They hired Grant. Since then, the managers feel they've witnessed something amazing, and Grant feels as if he's finally gotten the chance he's been waiting for his whole life.

When Patti Gibson, who coordinated the mural effort for the center, went looking for someone to paint the 2,600-square-foot wall, muralists told her it would take at least six weeks and cost more than $20,000. The center didn't want to spend that much money or time. So she called Grant, a 42-year-old artist who specializes in painting backdrops for corporate events and theater productions. Used to working under tight deadline pressures, he told her he would do it in one week for less than $10,000. Gibson thought he'd take at least two or three weeks no matter what he promised. After all, the Park Authority's own four-man crew took about four days just to paint the wall with an undercoating.

But just before the Labor Day weekend, Grant, of Arlington, put on the finishing touches after seven days of painting from dawn till nearly midnight. The result, say patrons and staff, is a dazzling work of art.

"Everyone is in awe," Gibson said. "It makes you feel like you're right there."

On the wall, a soothing turquoise on the left flows into a rich deep blue on the other end. Two killer whales, 18 feet and 30 feet long, float in the middle. Those who have seen it say they feel they can swim among the submerged ruins. The center's aquatics supervisor loves dolphins, so there are a good number of them in the picture especially for her.

Grant planned to have an ancient-looking statue sticking out of the sand in his mural. That, he felt, would drive home the feeling of a lost civilization. But the center's managers felt a bare-chested male bust in the picture might be too risque for a public pool, so it was removed.

For Grant, the work has been a physical challenge. It's the largest piece he's done. And the laborious process of painting the large space left him with blistered hands and an exhausted body.

Grant had other unique obstacles. Every seven inches, he had to work around the indentations at the edge of each block. At one spot, Grant had to paint a large drainage pipe running down one side of the wall, making it blend in with the rest of the mural. And because the pool room will be highly humid, he had to make sure every single part of the wall was covered with paint so no water would get underneath the mural.

"I want [patrons] to be blown away," Grant said. "I want them to be interested enough to walk up and look at the details and to look at the fish and coral."

The entire process also has been an education for Grant. It's the first time he's used industrial-strength acrylic paint, strong enough to withstand the pool's environment. All around were photos and books he'd brought to help him. There were textbooks on classical Greece, underwater pictures from an old copy of National Geographic and snapshots he took at the aquarium in Baltimore.

But while the project was the most challenging he's undertaken, it also was the most satisfying, he said. Unlike his theatrical and commercial backdrop works, this won't be taken down when the event is over.

And he said that, compared with his other assignments, this one gave him enough time to properly research and execute the mural.

The piece is something Grant has been working toward since he finished studying art in Pittsburgh. He realized by then that he preferred working on large pieces and that he felt more comfortable painting from a scaffold than at an easel.

While living in Germany briefly, he did some backdrops for a couple of plays and found that it allowed him the space he needed for the broad brush strokes he likes.

When he returned to the United States in 1988, he decided to settle in the Washington area and specialize in that kind of work, eventually heading up Britten-Grant Event Design in Ashburn.

But the recreation center project has shown him that large-scale murals are what he'd prefer doing full time. The center staff may be able to help him toward that goal. The managers like his work so much that they're thinking about having him do the opposite wall with another aquatic scene.

"The beauty of swimming is that it's soothing and tranquil," Grant said. "I hope this mural contributes to a feeling of vigorous tranquillity and makes people have that warm and fuzzy feeling when they're in the water."

CAPTION: Workers at Wakefield Recreation Center in Annandale work on the drained pool bottom as mural artist Tim Grant adds finishing touches to his undersea mural of Atlantis.

CAPTION: Grant worked from dawn until midnight for seven days to paint the mural on a wall by the indoor swimming pool.

CAPTION: Grant included a variety of aquatic life in his undersea mural, from tiny ones to killer whales.