Leacock began working on British documentaries in the mid '30s, and over the '40s helmed several documentaries, including Island People and Life in Her Hands. He helmed his first narrative feature in 1952, and by the end of the deacde came to Hollywood, where he continued to make features and also began working regularly for television. His notable films include the British dramas The Kidnappers (aka The Little Kidnappers) and Escapade, and the American-made Let No Man Write My Epitaph and The War Lover. He directed chiefly for television by the '60s.