Paris Hilton (search) showed us a revamped version of the classic one-piece bathing suit in her steamy Carl's Jr. ad, but she's not the only celebrity saying, "That's hot."
The girls of Wisteria Lane were actually the first stars to blow the whistle on this poolside trend. When the "Desperate Housewives" (search) graced the cover of Vanity Fair this spring, they made one thing clear to bathing beauties everywhere: the one-piece is back and more glamorous than ever.
"The one-piece bathing suits of today definitely are a reflection of America's taste for retro lifestyle and retro fashion," said Joshua Curtis (search), author of "Sunkissed: Swimwear and the Hollywood Beauty 1930-1950."
"The movie star glamour of yesteryear is creeping into the mainstream with celebrities such as (pop star/fashion designer) Gwen Stefani (search) leading the way."
Big and Bold: The Key Summer Accessories
For skeptics, the one-piece may conjure images of the modest '20s swimsuit. But these suits aren't the knitted wool tanks of that decade; they're actually sexier versions of the suits that pin-up girls like Marilyn Monroe (search) and Betty Grable (search) wore in the '40s.
"Very sexy versions of the one-piece can be even sexier than a two-piece," said Elycia Rubin (search), lifestyle director of C Magazine and author of "Frumpy to Foxy in 15 Minutes Flat."
Skimpy one-pieces don't leave as much to the imagination as the classic suits once did. Plunging necklines, playful-yet-racy cutouts and high-cut legs (the features of Paris' now-infamous suit) are making some one-pieces look more vixen than vintage.
"Our one-pieces are a sexier version that shows more skin," said Rebecca Greenblatt, head of public relations at Shoshanna, a fashion label known for its cute bathing suits and headed by Jerry Seinfeld's ex-girlfriend.
Low v-necklines and vertical seams on the bust are also making this season's swimwear more flattering than ever, proving that more coverage can be just as sexy as a teeny-weeny bikini.
"What I feel is a sexy look for women are bikinis because they show more skin — which is always a nice feature. At the same time, one-pieces can be flattering on women as well because they define the contours of a woman's body well," said 21-year-old Marcello Palombi of Washington, D.C.
This summer it's not just about a sexy cut, it's also about details. The trendier one-pieces look more "bling" than ever with shining sequins and studs.
Snaps, buckles, bows and ruffles also give suits a retro flair. Look for suits with asymmetrical details like big rings or buckles on only one hip or shoulder.
"We're adding more embellishments: bamboo rings, beading and crochet," Greenblatt said.
There's also more fabric with one-pieces — meaning more creative patterns, colors and cuts to reflect a woman's personal style.
Halter-style suits are always popular, but expect to see sash ties stepping in where spaghetti strings once dominated.
But with all the added flair this season, color hasn't been neglected. Many of the one-pieces still have patterns and bright splashes of color. Preppy colors are popular, keeping in line with many of the sweet and girly poolside looks. Pinks and greens and pastels paired with chocolate are prominent.
"The heyday of the bold pattern and print suits was indeed the 1940s; however, bold colors, like fluorescents, dominated from the '60s through current day," Curtis said.
Retro prints such as polka dots, candy stripes, paisley and florals as well as gathered fabric and trim are also popular this summer.
As for two-pieces, even if you're not as "twiggy" as some of the original trendsetters, it doesn't get more nostalgic than the tie-dyed suits that have made a comeback this season.
"The polka dot-patterned bra top with an eyelet and our rainbow colored tie-dyed suit have been very popular," Goldblatt said.
Swimmers can get a more sophisticated look by keeping the suit simple and sleek. But not every one-piece reveals a flawless silhouette. This is partially because one-pieces can be difficult to fit correctly.
The one-piece "can be a lot trickier to fit, because not everyone is the same shape on top as they are on bottom. We've recently introduced longer tankinis (search) to our line, which are great because they give the coverage of the one piece, with the ease of separate sizes and styles," said Susie Bickford, retail analyst for Malia Mills, a swimsuit label known for its different-sized tops and bottoms and mix-and-match styles, colors and prints.
Malia Mills says sales of the tankini — which allows for tummy tanning and looks attractive on a variety of builds — are rising this year, another nod to the unified suit movement.
Even Speedo, the company synonymous with sport, is diving into the retro one-piece trend. They now have styles for the more fashionable sunbather, too.
And a more active-cut suit may be a good idea for those who want to tone up a bit before donning one of the skimpier one-pieces, which can show even the slightest imperfections.
But have no fear, eensy-weensy bikini fans. Swimsuit experts say that while the one-piece has made a very strong return this summer, two-pieces are still going strong.
Said Bickford: "The bikini will always stay on top!"