Best DressedRihanna, Katy Perry & More Grammys 2012 Red-Carpet Looks (Photos)02.13.12Best DressedRihanna, Katy Perry & More Grammys 2012 Red-Carpet Looks (Photos)Rihanna stunned in Armani, Fergie gave viewers an eyeful in an orange lace dress, and Katy Perry went back to blue. See the best dressed on music’s big night.02.13.12 5:00 AM ETRihanna stunned in Armani, Fergie gave viewers an eyeful in an orange lace dress, and Katy Perry went back to blue. See the best dressed on music's big night. Jason Merritt / Getty ImagesNicki MinajThe rapper, nominated for Best New Artist, wore an enormous (and puzzling) black-beaded red Versace cape, complete with satin gloves and a date dressed to resemble the pope. Joe Klamar, AFP / Getty ImagesEsperanza SpaldingLast year’s winner of the Best New Artist award wore a multicolor multitiered dress. Jason Merritt / Getty ImagesTaylor SwiftThe country-pop superstar showed off her long, lean figure in a Dolce & Gabbana nude silk mermaid gown. Jason Merritt / Getty ImagesAlicia KeysThe singer, who delivered a tribute to Etta James with Bonnie Raitt, wore a black cap-sleeve Alexandre Vauthier dress with a V-shaped gold neckpiece and Christian Louboutin heels. Jason Merritt / Getty ImagesRihannaThe singer wore a unique black Giorgio Armani dress with a plunging neckline and high slit. She and Mr. Armani collaborated to create the dress, which was complemented by an 18mm Cordelia chain necklace by David Yurman. Joe Klamar, AFP / Getty ImagesAdeleThe Grammy darling made her post-throat-surgery return to the stage in a shimmering black Armani gown. She also wore a white-gold and diamond ring and earrings by Cartier. Jason Merritt / Getty ImagesKate BeckinsaleThe actress showed off some leg in a cream silk minidress by Zuhair Murad and earrings by Sutra. Jason Merritt / Getty ImagesKelly OsbourneSporting lavender locks and a bright smile, Kelly Osbourne took to the red carpet in a glittering beaded dress by Tony Ward, shoes by Giuseppe Zanotti, and jewelry by Pomellato. Jason Merritt / Getty ImagesCarrie UnderwoodThe country singer donned a Gomez-Gracia starlet gown and carried Swarovski’s black-crystal Pure clutch. Jason Merritt / Getty ImagesBruno MarsThe singer combed his hair up to new heights and looked dapper in a gray three-piece suit by Dolce & Gabbana. Jason Merritt / Getty ImagesFergieThe singer went for a transparent look, wearing an orange lace Jean Paul Gaultier dress, Neil Lane gold, and black underwear and bra. Jason Merritt Getty ImagesKaty PerryThe pop songstress wore a trailing blue sequined gown by Elie Saab with (of course) dyed-blue locks to match, Christian Louboutin heels, and a reported $2 million worth of jewels from Norman Silverman. Jason Merritt / Getty ImagesSteve Martin and the Steep Canyon RangersSteve Martin, of Steve Martin and the Steep Canyon Rangers, wore a light-gray suit and black-rimmed glasses. Steve Granitz, WireImage / Getty ImagesSashaNext to Nicki Minaj's live pope date, Russian dance-pop singer Sasha Gradiva easily had the most interesting accessory of the night: huge guns covering her entire right arm.