X-Men: Days of Future Past is a 2014 American superhero film based on the fictional X-Men characters that appear in Marvel Comics. Directed by Bryan Singer, it is the seventh installment of the X-Men film series and acts as a sequel to both 2006's X-Men: The Last Stand and 2011's X-Men: First Class. The story, inspired by the 1981 Uncanny X-Men storyline "Days of Future Past" by Chris Claremont and John Byrne, focuses on two time periods, with Wolverine traveling back in time to 1973 to change history and prevent an event that results in doom for both humans and mutants. The film features an ensemble cast, including Hugh Jackman, James McAvoy, Michael Fassbender, Jennifer Lawrence, Halle Berry, Anna Paquin, Ellen Page, Peter Dinklage, Ian McKellen, and Patrick Stewart. Simon Kinberg wrote the screenplay from a story he conceived with Jane Goldman and Matthew Vaughn.
Vaughn had directed First Class and was set to return in Days of Future Past before leaving for Kingsman: The Secret Service. Thus Singer, who had directed the first two X-Men films, made his return as a director, and brought along most of the crew from those productions. With a budget of $205 million, principal photography began in Montreal, Quebec in April 2013 and concluded in August the same year, with additional filming and pick-ups taking place in November 2013 and February 2014. Twelve companies handled the visual effects.