The Master is a 2012 American psychological drama film written and directed by Paul Thomas Anderson and starring Joaquin Phoenix, Philip Seymour Hoffman, and Amy Adams. It tells the story of Freddie Quell (Phoenix), a World War II Navy veteran struggling to adjust to a post-war society, who meets Lancaster Dodd (Hoffman), the leader of a cult known as The Cause. Dodd sees something in Quell and accepts him into the movement. Freddie takes a liking to The Cause and begins traveling with Dodd's family to spread his teachings.

The film was produced by Annapurna Pictures and Ghoulardi Film Company and distributed by The Weinstein Company. The film's inspirations were varied: it was partly inspired by Scientology founder L. Ron Hubbard, by early drafts of Anderson's There Will Be Blood, the novel V. by Thomas Pynchon, drunken Navy stories that Jason Robards had told to Anderson while filming Magnolia, and the life story of author John Steinbeck. The Master was shot almost entirely on 65mm film stock, making it the first fiction feature to be shot and released in 70mm since Kenneth Branagh's Hamlet in 1996.

Initially, the film was set up with Universal Pictures, but fell through due to script and budget problems. It was first publicly shown on August 3, 2012, at the American Cinematheque in 70 mm and screened variously in the same way, before officially premiering at the Venice Film Festival on September 1, where it won three awards: the FIPRESCI Award for Best Film; the Silver Lion for Anderson's direction; and the Volpi Cup for Best Actor, shared by Phoenix and Hoffman. It was released in theaters in the United States on September 14, 2012, to critical acclaim; its performances (particularly those from the three leads), screenplay, direction, plausibility, and realistic portrayal of post-World War II Americans were praised.

Considered one of Anderson's finest works and one of the best films of the 2010s, it received three Oscar nominations: Best Actor for Phoenix, Best Supporting Actor for Hoffman, and Best Supporting Actress for Adams. In 2016, The Master was voted the 24th greatest film of the 21st century by 177 critics from around the world. Anderson has repeatedly stated that The Master is his favorite film of those he has made.