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Looking drop-dead sexy in a very low-cut black silk custom Giorgio Armani gown with a thigh-high slit and a mermaid train, Rihanna stole the show on the red carpet at the 2012 Grammy Awards in LA, on Sunday evening.

The S&M singer, who's set to perform at tonight's awards ceremony, paired her daring gown with Neil Lane jewels, Jacquie Aiche body necklaces, Christian Louboutin stilettos, and a Jimmy Choo clutch.

This show marks the first time Rihanna and ex-bf Chris Brown have appeared at the same awards show since his attack on her in 2009, which was also on the eve of the Grammys that year.