Robert Downey Jr. and Jay Baruchel are set to star in Ben Stiller's comedy, Tropic Thunder for DreamWorks Pictures and Red Hour Films.

Stiller is producing, directing and co-writing the screenplay with Justin Theroux and Etan Cohen. The Hollywood Reporter notes in the film, everything goes wrong during the making of a big-budget war movie, and the actors end up becoming the commandos they are playing. Downey will play Kirk Lazarus, the greatest actor of his generation and a four-time Oscar winner. Baruchel will play Kevin Sandusky, an unknown actor on the set.

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Shooting on Tropic Thunder is set to start in July.