I consider Robert Weine’s Das Cabinet des Dr. Caligari (1920) (translated: The Cabinet of Dr. Caligari) to be required viewing, which is not an honor I hand out often, despite my somewhat lax criteria for what makes an enjoyable film.
This one takes just the cake. It is German expressionism at its best, and should be viewed once a year at the very least.
I don’t want to give away the plot, because this film is best viewed for the first time with absolutely no information about what is going on. I will tell you that there is an oddly lovable somnambulist involved, a few utterly creepy characters who lurk in the highly-contrasted shadows, and that the film is billed as a horror.
Even for those who aren’t fans of the horror genre, it should be apparent that this film is a complete masterpiece. Every single performance is fantastic, with Conrad Veidt being particularly impactful. These performances combined with fantastic set design and direction give the film an artistic brilliance that leaves the viewer stunned. As a result, Das Cabinet is the type of film that sticks with you after watching.
Das Cabinet is available on Netflix, both instant and on DVD. I recommend instant viewing, as I’m not sure which DVD release they send out — some versions are better than others. The streaming version is well-restored and contains intertitles in English.