Tom Cruise amazed co-stars with his fancy footwork in "Tropic Thunder."

The actor plays a balding computer geek and studio boss in the new comedy, and performs a hip-hop dance for party guests during his brief cameo.

The British film director, who is battling constant rumors his marriage to Madonna is in trouble, spent the afternoon with Robert and his spouse Susan at the lavish Beverly Hills Hotel.

A source told Britain's Daily Express newspaper: "Guy was having a low-key meal by the pool with the Downeys. He was eating slowly and seemed dispirited."