They Were Expendable is a 1945 American war film directed by John Ford, starring Robert Montgomery and John Wayne, and featuring Donna Reed. The film is based on the 1942 novel of the same name by William Lindsay White, relating the story of the exploits of Motor Torpedo Boat Squadron Three, a United States PT boat unit defending the Philippines against Japanese invasion during the Battle of the Philippines (1941–42) in World War II.

Robert Montgomery (; born Henry Montgomery Jr.; was an American actor, director, and producer. He began his acting career on the stage, but was soon hired by MGM. Initially assigned roles in comedies, he soon proved he was able to handle dramatic ones, as well. He appeared in a wide variety of roles, such as the weak-willed prisoner Kent in The Big House, the psychotic Danny in Night Must Fall, and Joe, the boxer mistakenly sent to Heaven in Here Comes Mr. Jordan. The last two earned him nominations for the Academy Award for Best Actor.