The Whole Truth is a 1955 thriller play by the British writer Philip Mackie.
Originally written and broadcast by the BBC as a television play, it was rewritten for the stage the same year. It premiered at the Royal Lyceum Theatre in Edinburgh, before beginning a 145 performance West End run at the Aldwych Theatre. The original cast included Leslie Phillips, Ernest Clark and Sarah Lawson.
In 1958 it was made into a film The Whole Truth directed by John Guillermin starring Stewart Granger and Donna Reed and George Sanders.