Sherlock Holmes: A Game of Shadows is a 2011 period mystery action film and a sequel to the 2009 film Sherlock Holmes. The film is directed by Guy Ritchie and produced by Dan Lin, Joel Silver, Lionel Wigram and Susan Downey.

The film's screenplay was written by Kieran Mulroney and Michele Mulroney. Robert Downey Jr. and Jude Law reprise their roles as Sherlock Holmes and Dr. John Watson, respectively, alongside Noomi Rapace as Madame Simza "Sim" Heron, Jared Harris as Professor Moriarty, Stephen Fry as Mycroft Holmes, Kelly Reilly as Mary Morstan, Eddie Marsan as Inspector Lestrade, William Houston as Constable Clark and Rachel McAdams as Irene Adler. Although the film follows an original premise, it incorporates more closely elements of Conan Doyle's short stories, including "The Final Problem" and "The Adventure of the Empty House". In the film, Holmes and Watson travel across Europe with a Romani fortune-teller to foil an intricate plot by the cunning Professor Moriarty to instigate a major European conflict.

Though the film received predominantly mixed reviews from critics, with praise for the action sequences and the performances of Downey, Law, and Harris, criticism over the poor use of its supporting cast, particularly McAdams, it was commercially successful, with a worldwide gross of over $543 million. A third film to be directed by Dexter Fletcher is currently in development hell.