Murnau is one of those directors who has always fascinated me. After serving in the German army during the First World War, he made the terrifying horror film Nosferatu, based on Bram Stoker's Dracula. He later filmed the innovative comedy The Last Laugh as well as his re-imagining of Tartuffe, before adapting for film what is probably an even more famous play, Goethe's Faust.
Herr Tartüff really is a reimagining, as it departs significantly from Molière's play. The film uses a framing device in which an old man is being slowly poisoned by his housekeeper. The old man's grandson comes for a visit, but gets thrown out for being a good-for-nothing actor. Being an actor, however, he is able to disguise himself and visit the house with a traveling cinema. He then shows a film based on Tartuffe and exposes the housekeeper's hypocrisy.
That just stretches the action out longer, though, as the film has another scene that takes place that night, where Orgon's wife Elmire goes even further with Herr Tartüff, this time in a room that contains a bed! The faithful maid Dorine forces Orgon to watch through a keyhole, though, and the impostor is unmasked.
Lil Dagover, who played the heroine in The Cabinet of Dr. Caligari, takes on the part of Elmire, and is stunning in the role. If you're interested, you can watch the whole film here.