Sport requires narrative. It relies on a deepening relationship between athlete and fan, the playing out of rivalries, a shared history of success and defeat.

In this, Olympic swimming faces special difficulties. For 47 months in a row, it doesn’t register with the public. Then, in the 48th, we’re expected to embrace a cast of lanky unknowns and become conversant in such minutia as stroke efficiency and relay starts.

Fortunately, this year’s Olympic swimming competition promises drama and achievements whose value is self-evident.The U.S. men’s team is touted as the best since 1976; its biggest star, 19-yearold Michael Phelps, means to rewrite history by improving upon Mark Spitz’s seven-gold-medal showing at the 1972 Games in Munich. (In one of the crasser commercial gestures in Olympic history, Speedo is offering a $1 million prize if Phelps succeeds.)

To understand the audacity of Phelps’s goal, it may help to put it in a more familiar context. Imagine a baseball player, unproven in the postseason – albeit with one hell of a slugging average going in – predicting that he’ll match Reggie Jackson’s Game 6 World Series feat of three homers in three swings. This is what Phelps means to do in swimming: Repeat the sport’s most dramatic accomplishment on its grandest stage.

Of course, swimming is far more predictable than baseball. Although the margins of victory – typically tenths or hundredths of seconds – may sound vanishingly small, they are remarkably stable. Swimmers at this level know their events so well and have swum them so often that they can reproduce races, down to number of strokes and split times, with uncanny accuracy.Given this, Phelps’s goal is still wildly ambitious, but not unattainable.

His dominance owes, first, to physiology. Phelps is not a new model of swimmer, as Ali was a new model of heavyweight or Shaq a new model of center, but a full realization of the classical form. Like the last son of Atlantis, he appears to descend from a line evolved especially for water.(His parents are actually a school administrator and former college football player from Baltimore).

He is 6-feet-4-inches tall, with an unusually long torso and tiny legs. His wingspan exceeds his height by three inches (for most people, the two are identical). His joints are hyper-flexible, enabling him to extend the sweep of his strokes and the range of his kick, and to flatten his ankles so that his feet become perfect flippers. In other words, the parts that propel him through the water are larger and better than normal, the parts that drag, smaller.

Phelps is also said to have supernatural “feel for the water” – swimspeak for the ability to carve your way efficiently through the stuff – and to recuperate exceptionally quickly after a race, which makes possible his grueling Olympic schedule.The only chink in his armor is his sluggish block start: Phelps always gives his opponents a head start.

Phelps will compete in five individual events in Athens – the 200- and 400-meter individual medley, the 100- and 200-meter butterfly, and the 200-meter freestyle – and up to three relays. Of these, the most exciting events may be his weakest.

Like the videogame showoff at the local arcade, Phelps owns the top seven times in his signature event, the 200 meter I.M., which requires the swimmer to complete one length of the pool in each of the four competitive strokes (butterfly, backstroke, breaststroke, and freestyle). The closest anyone has come to his world record mark of 1:55.94 is 1:58.16. He also holds world records in the 400 I.M. and 200 butterfly.

A better race, in terms of spectatorship, may be the 100 butterfly, where Phelps was edged out at the U.S. Olympic trials by Ian Cocker, who bettered his own world record in the bargain. But the event that is getting all the attention – the one Australian papers are billing “the race of the century” – is the 200-meter freestyle. Facing Australian great Ian Thorpe and defending Olympic champion Pieter van den Hoogenband of the Netherlands, Phelps enters the race a decided underdog – an unusual position for him, but one he relishes.

The other men on the U.S. Team exist only in the thin patches of sunlight around Phelps’s enormous shadow, though many dominate their individual events. At the U.S. Olympic trials, Brendan Hansen broke world records formerly held by Japan’s Kosuke Kitajima in both the 100-and 200-meter breaststroke.Aaron Piersol set a new world mark in the 200-meter backstroke and stole the 100 from Olympic teammate and world-record hold er Lenny Krazelberg.

Flamboyant sprinter Gary Hall Jr. qualified in only one individual event this year, the 50-meter freestyle – he will also swim the 4 x 100 freestyle relay – but he’s sure to make a grand show of it.The 50 freestyle is the heavyweight championship of swimming, the contest to decide the fastest man alive (in water).

The heavyweight comparison is one Hall encourages by wearing an Everlast boxing robe on the pool deck and kissing his biceps before racing. Hall will face a familiar cast of international sprinters – led by an aging but not necessarily outmoded “Russian Rocket,” Aleksandr Popov – and fellow American Jason Lezak, who won the 100-meter freestyle at the U.S. Olympic trials.

The women’s team has fewer individual standouts, but looks stronger in relays. Leading the way is 21-year-old Natalie Coughlin, an athlete many in the swimming community consider the equal of Phelps.

Coughlin has dominated American collegiate swimming in half-a-dozen events for several years, but after a disastrous World Championships last summer – she raced a full schedule with a fever – she has scaled back her Olympic ambitions. She will swim only three events: the 100 backstroke (in which she holds the world record), the 100 freestyle, and the 4 x 100 freestyle relay.

Amanda Beard is best remembered as the teddy-bear toting 14-year-old who won silver in the 100- and 200-meter breaststroke in the Atlanta Games. After 1996, she underwent a “13 Going On 30” transformation, growing seven inches and gaining 25 pounds almost overnight.

Now a womanly 22, Beard has refashioned her stroke to take advantage of improved upper-body strength, and is poised to win the 200 breaststroke and medal in the 100, where she’ll face Australian world record holder Liesel Jones.

In the something-old-something-new category are Jenny Thompson and Katie Hoff. Thompson, a seven-time Olympic gold medalist in relays,is a sentimental favorite, competing in her fourth Olympic Games at age 31. Hoff, meanwhile, is rated no. 1 in the world in the 400 I.M. at the tender age of 15.