Transformers: Dark of the Moon is a 2011 American science fiction action film based on Hasbro's Transformers toy line. The film is the third installment of the Transformers film series and the sequel to Transformers: Revenge of the Fallen (2009). The film is directed by Michael Bay and written by Ehren Kruger. It stars Shia LaBeouf, Josh Duhamel, John Turturro, Tyrese Gibson, Kevin Dunn, and Julie White, reprising their roles from the previous films. New cast members including Rosie Huntington-Whiteley, Patrick Dempsey, John Malkovich, and Frances McDormand. In the film, Optimus Prime, Bumblebee, and Sam Witwicky must lead the Autobots against Megatron and the Decepticons as they battle to possess powerful technology abandoned on the Moon, in order to restore Cybertron.

Development of a third Transformers film began by May 2007. The film employed both regular 35 mm film cameras and specially-developed 3D cameras, with filming locations in Chicago, Florida, Indiana, Milwaukee, Moscow, and Washington, D.C. The film was 3D rendered specifically for 3-D, and the visual effects involved more complex robots which took longer to render. Dark of the Moon's release date was moved from July 1 to June 29, in order to monitor an early response to footage.

Exclusive early premieres took place on June 28, 2011 by Paramount Pictures, one night before worldwide release. The film received mixed reviews from critics and grossed $1.124 billion worldwide. It became the fifth highest-grossing film in history at the time, the second highest-grossing film of 2011, Bay's highest-grossing film, and the highest-grossing film in the franchise to date. Like the first film, it was nominated for Best Sound Editing, Best Sound Mixing, and Best Visual Effects at the 84th Academy Awards. It was followed by Transformers: Age of Extinction in 2014.