Brad Pitt, Johnny Depp, Antonio Banderas, Sean Penn all making the journey
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'Tree of Life' star Sean Penn
Why he'll be at Cannes: Penn is co-starring, along with Brad Pitt, in Terrence Malick's highly-anticipated "Tree of Life." Malick also directed Penn in 1998's WWII drama "The Thin Red Line.' Plus, Penn loves the paparazzi.