Our PicksBest and Worst Dressed of the WeekThe Fashion Beast Team03.07.14Our PicksBest and Worst Dressed of the WeekJennifer Lawrence sparkles in Tom Ford, Rihanna rocks red mink and suspenders, and Serena Williams shows off cleavage in too many places. Plus, more best and worst dressed of the week.The Fashion Beast Team03.07.14 10:45 AM ETGettyThe Best & Worst DressedJennifer Lawrence sparkles in Tom Ford, Rihanna rocks red mink and suspenders at Paris Fashion Week, and Serena Williams shows off cleavage in way too many places. Plus, more best and worst dressed of the week. Patrick Kovarik/AFP/GettyBest Dressed: RihannaBad gal Ri-Ri pulled a high-fashion Elmo while sitting front row at the Christian Dior Fall/Winter 2014 show on February 28. The singer rocked a red mink coat over a black silk minidress, suspenders, and stocking, all by the brand. Adrian Sanchez-Gonzalez/AFP/GettyBest Dressed: Jennifer LawrenceJennifer Lawrence may have stunned in Christian Dior at Sunday's Academy Awards, but the real look of the night came at the Vanity Fair After Party, where the actress sported a long-sleeve, taupe mini-dress by Tom Ford with silver, glass-like embellishments. Francois Guillot/AFP/GettyBest Dressed: Keira KnightleyFor Chanel's Fall/Winter 2014 show on March 4, actress Keira Knightley showed off her itty-bitty waist in a black and white illusion crop top and skirt, gold pointed-toe heels, and a quilted bag, all by the brand. Anthony Harvey/GettyBest Dressed: Rita OraRita Ora stunned at the Vanity Fair Oscar Party on March 2 in a white lace dress with Swarovski crystal detailing on the neckline by Miu Miu. She accessorized with silver Manolo Blahnik pumps and a white Jimmy Choo clutch. Jacopo Raule/GC Images, via GettyBest Dressed: Olivia PalermoOlivia Palermo kept things simple and sweet in a white Peter Pan-collared frock with a pleated bottom and an oversized blue pearl necklace at the Christian Dior Fall/Winter 2014 show on February 28. Pascal Le Segretain/GettyBest Dressed: Giovanna BattagliaGiovanna Battaglia looked sophisticated in a light green poncho and grey turtleneck at the Louis Vuitton Fall/Winter 2014 show on March 5. Pascal Le Segretain/GettyBest Dressed: Sienna MillerSienna Miller's accessories made a statement at the Vanity Fair Oscar Party on March 2. The actress layered six gold cuffs up her arm while carrying a black and white 'Skull' clutch, adding a heavy dose of bling to her red, strapless Alexander McQueen gown. Pierre Suu/GettyWorst Dressed: Cara DelevingneCara Delevingne stepped out after the Stella McCartney show on March 3 in a patterned tracksuit and a fishnet bra. Is she going for a high-fashion homeless look? Pascal Le Segretain/GettyWorst Dressed: Serena WilliamsTennis star Serena Williams took a major risk at the Vanity Fair Oscar Party on March 2, and it didn't pay off. The cut-out Michael Costello dress showed off cleavage in strange places, and the flower print was too pink and glittery for the event.