Das Geheimnis der grünen Droge

I Thank a Fool is a 1962 British Metrocolor crime film made by Eaton (De Grunwald Productions) and Metro-Goldwyn-Mayer in CinemaScope. It was directed by Robert Stevens and produced by Anatole de Grunwald from a screenplay by Karl Tunberg based on the 1958 novel of the same title by Audrey Erskine Lindop. The music score was by Ron Goodwin and the cinematography by Harry Waxman.

The film stars Susan Hayward and Peter Finch with Diane Cilento and Cyril Cusack. Also in the cast are Kieron Moore, Richard Wattis, Athene Seyler, Miriam Karlin, Laurence Naismith, J. G. Devlin, Clive Morton, Richard Leech and Brenda De Banzie.