The Secret of NIMH is a 1982 American animated fantasy adventure film directed by Don Bluth in his directorial debut and based on Robert C. O'Brien's children's novel, Mrs. Frisby and the Rats of NIMH. Featuring an ensemble cast consisting of Elizabeth Hartman in her final film role as its protagonist, Mrs. Brisby, with Peter Strauss, Arthur Malet, Dom DeLuise, John Carradine, Derek Jacobi, Hermione Baddeley and Paul Shenar in supporting roles, the film was produced by Bluth's production company, Don Bluth Productions in association with Aurora Productions.

Plot

Mrs. Brisby, a widowed field mouse, lives in a cinder block with her children on a farm owned by the Fitzgibbons family. She intends to move her family out of the field as plowing time approaches, but her son Timothy has fallen ill, making it impossible for him to travel.