The Key is a 1958 British-American war film set in 1941 during the Battle of the Atlantic. It was based on the 1951 novel Stella by Jan de Hartog (later republished as The Distant Shore and The Key) and was directed by Carol Reed. William Holden, Sophia Loren and Trevor Howard starred in the production.

The key to a flat in wartime Britain may augur bad luck for a succession of tug captains of the Royal Navy whose task is to rescue crippled ships in "U-boat Alley." As each takes possession from his unfortunate predecessor, the flat's other occupant, a Swiss expatriate named Stella, apparently comes with it. The latest captain struggles with his conflicting fears and affection for its apparent jinx.