Events: The 2009 Costume Institute Gala

Grammy winner Rihanna arrives at the Costume Institute Gala at the Metropolitan Museum of Art in New York City on May 4th. The annual soiree bought out a star-studded crowd and this year's theme was, “The Model as Muse: Embodying Fashion”.

The "Take A Bow" songstress made her first red carpet appearance, since her drama with Chris Brown back in February, and took on a feminized version of the classic black tuxedo with her Dolce & Gabbana get-up. She definitely got the attention that she was trying to garnish, unfortunately the reason isn't positive, since her attire is a complete disaster.

Justin Timberlake sported a classic tux from his own William Rast line, while his lady love, Jessica Biel, opted for a Atelier Versace gown and sexy stilettos. Justin looks great, as always, and the glasses only add to his sexiness, but Jessica's billowing dress is just unflattering, especially for a woman with one of the best bodies in Hollywood.

Eva Longoria kept it sleek and sexy in a dreamy Diane von Furstenberg dress, while walking the red carpet with her husband Tony Parker. As it has often been said, "less is more", and this look proves it.

Ciara donned a sleek dress by Emilio Pucci's Peter Dundas, that complimented her sexy, toned body.

Jesse McCartney and Katy Perry, in a silk Tommy Hilfiger halter dress, posed for the cameras. Jesse's suit could have used a good ironing/steaming, while Katy's look, for her, is an improvement.

Kerry Washington walked the carpet in a lacey Louis Vuitton ensemble that was just down right hideous, while Kanye West and his girlfriend Amber Rose smiled for the cameras.

Blake Lively showed off her gorgegous legs with a mesmerizing split in a teal gown from Versace's Spring/Summer collection. Loves it.

Victoria Beckham put her best fashion foot forward in a Marc Jacobs one-shoulder polka dot frock complete with train. The sexy mama just has a confidence that allows her to pull off virtually anything, this included.

Jessica Alba wore a a bright blue, black, and green mini by Jason Wu, who also designed Michelle Obama's inaugural gown. A simple look, in fact, almost too simple for a prestigious event, plus the leggings kill it.

Actressed Kate Hudson, Liv Tyler, and Kate Bosworth hit the red carpet in gowns designed by Stella McCartney, while Eva Mendes shimmered in a simple yet chic Calvin Klein creation.

Tyra Banks donned a strapless black Badgley Mischka creation, that was beautiful, but overshadowed by her disasterous choices in hair and makeup.

Giselle Bundchen, with husband Tom Brady, strutted in a sequined mini, courtesy of Versace, which she paired with gawdy heels.

Madonna, grabs Celebrity Bug's Worst Dressed title, with her horrifying Louis Vuitton ensemble, which she paired with bunny ears, fingerless gloves, and lace-up patent leather boots.

The Olsen Twins, Mary-Kate (right) and Ashley (left), were on opposite ends of the spectrum, as Ashley shined in a dramatic white gown from her sister's line and Mary-Kate looked ridiculous in a Christian Lacroix couture gown.

A pregnant Heidi Klum, donned a navy blue J. Mendel gown, that covered her baby bump. To put it simply, there are tons of beautiful maternity dresses, but this isn't one of them.

Anne Hathaway paired a purple poofed Marc Jacobs frock with a retro do and and strappy, silver heels. The color of the dress compliments her well, but the cut is absolutely horrible.

Celebrity Bug's Best Dressed:
Eva Longoria, Blake Lively, & Justin Timberlake.

Celebrity Bug's Worst Dressed:
Madonna, Kerry Washington, & Mary-Kate Olsen.