The Third Alibi is a 1961 British 'B' thriller film directed by Montgomery Tully and starring Laurence Payne, Patricia Dainton, Jane Griffiths and Edward Underdown. The screenplay is by Maurice J. Wilson and Tully, based on the play A Moment of Blindness by Pip and Jane Baker.

Cleo Laine (billed as a guest star) is seen singing a musical number during a brief sequence set in a theatre; her piano accompanist is an uncredited (and unspeaking, though clearly visible) Dudley Moore, in his first film role.