Johnny Depp, Guitarist, Surprises Crowd at Tom Petty Tribute Show

This story first appeared in the Nov. 30 issue of The Hollywood Reporter magazine.

The crowd at the El Rey Theatre on Nov. 14 was expecting musicians to drop in to jam at Petty Fest, a charity event for the Sweet ReliefMusicians Fund where celebs covered Tom Pettys greatest hits.

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Members of The Strokes, The Black Keys and Kings of Leon all rocked out, but nobody expected Johnny Depp -- a friend of Petty -- to show up and play guitar on Mary Janes Last Dance, with Ke$ha on vocals.

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And Depp even hung out afterward. He was looking pretty cool, says Nick Valensi of The Strokes. Hes the closest thing to Keith Richards that youre going to get.

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The low point? When The Hangover and The New Normal star Justin Bartha sang Into the Great Wide Open off-key, then read the words out of a lyrics book.