Moonlighting Mistress or I Sleep with My Murderer (German: Ich schlafe mit meinem Mörder, French: Je couche avec mon assassin) is a 1970 French-West German thriller film directed by Wolfgang Becker and starring Harald Leipnitz, Ruth-Maria Kubitschek and Véronique Vendell. Resembling the fashionable giallo genre, it was produced by Rapid Film which specialised in making low-budget genre films with commercial appeal.
A man intends to kill his wealthy wife so he can inherit her money and live with his attractive mistress. However, scheme to murder her does not go to plan.