Caught in the Act

Rumer Willis: Budding Soul Singer?

02/23/2012 at 05:55 AM EST

Rumer Willis wants to prove she has more than acting chops: the 23-year-old surprised the crowd at Jason Scoppa's Corzo Sessions inside Hollywood's Sayers Club by singing some soulful tunes – specifically Peggy Lee's "Fever" and "Valerie," made famous by Amy Winehouse. A guest at the show says the starlet was with a group of friends and was "calm, casual and cool." As for her performance? Says the source: "She was a great singer and was totally badass," adding that she requested to perform the second song after "Fever" went off without a hitch. "– Jennifer Garcia

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