Lockout (also known as MS One: Maximum Security) is a 2012 English-language French science fiction action film directed by James Mather and Stephen Saint Leger from a script written by Mather, Saint Leger, and Luc Besson (with Besson serving also as executive producer through EuropaCorp). It stars Guy Pearce, Maggie Grace, Vincent Regan, Joe Gilgun, Lennie James and Peter Stormare. The film marks the feature directorial debut for both Mather and Saint Leger. The plot follows Snow (Pearce), a man framed for a crime he did not commit, who is offered his freedom in exchange for rescuing the President's daughter Emilie (Grace) from the orbital prison MS One, which has been taken over by its inmates, led by Alex (Regan) and his psychotic brother Hydell (Gilgun).

Lockout premiered on 7 April 2012 at the Brussels International Festival of Fantasy Film, and was released in North America and France in April 2012. The film received mixed reviews from critics, although Pearce's performance was praised.