Leo Gratten Carroll was an English actor. In a career of more than 40 years, he appeared in six Hitchcock films including Spellbound, Strangers on a Train and North by Northwest and in three television series, Topper, Going My Way, and The Man from U.N.C.L.E..

Strangers on a Train is a 1951 American psychological thriller film noir produced and directed by Alfred Hitchcock, and based on the 1950 novel Strangers on a Train by Patricia Highsmith. It was shot in late 1950, and released by Warner Bros. on June 30, 1951, starring Farley Granger, Ruth Roman, and Robert Walker.