Agatha is a 1979 British drama thriller film directed by Michael Apted and starring Vanessa Redgrave, Dustin Hoffman and Timothy Dalton. It was written by Kathleen Tynan. The film focuses on renowned crime writer Agatha Christie's famous 11-day disappearance in 1926. The film was released 9 February 1979, receiving generally positive reviews from critics, who praised the production values and performances.

At the 52nd Academy Awards for films from 1979, it received a nomination for Best Costume Design for Shirley Russell. The award, however, went to Albert Wolsky for All That Jazz.