Robert Downey Jr. is set to star as the main character in Sherlock Holmes, a reimagining of Sir Arthur Conan Doyle's sparky sleuth with Guy Ritchie directing for Warner Bros.

According to The Hollywood Reporter, the movie takes its cue from a forthcoming comic book that producer Lionel Wigram wrote as a selling tool for a new take on the classic character. The concept sees Holmes as more adventurous and less stuffy than previous screen incarnations and mines more obscure character traits.

Warners' Holmes project will have to contend with Columbia's Sherlock Holmes, this one starring Sacha Baron Cohen as the sleuth and Will Ferrell as his sidekick Dr. Watson. Judd Apatow is producing the comedy, which does not yet have a director attached.

Production will start in the fall. Warner is looking at an October 2009 release.

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