What set Caligari apart from other films of the period was the way in which it conveyed extreme psychological states through deliberately distorted visual imagery - it wasn't the first film to create an entirely new world, but it was certainly one of the earliest truly memorable attempts. Unlike many other films both before and since, the distortion is built into the set design, with deliberately skewed angles and painted shadows (and indeed painted patches of light) creating an overwhelmingly oppressive atmosphere riddled with insanity and paranoia.

Doctor Caligari is an avuncular yet strangely sinister figure who turns up one day in a small German town and wows the local populace with his hypnotic powers, as practiced on the somnambulist Cesare, a gaunt, pallid figure clad from head to foot in black. But it's not just an amusing stage act - once the curtain has come down and night has fallen, Cesare is manipulated by his master to altogether nastier ends...

Silent films can be notoriously badly served on the small screen - all too often, dreadful, decayed prints are shown at the wrong speed with an inappropriate music score - but this is way above average. The film has been transferred at the correct 18 frames per second, colour tinted according to the director's original guidelines, and with English titles designed in the style of the overtly Expressionist German titles that accompanied the first release of the film. The film was originally shot in 4:3, so you wouldn't expect an anamorphic transfer.

The high rating for picture quality is to acknowledge the obvious care taken in the preparation - no-one's going to pretend that the final result is going to give A Bug's Life a run for its money in the digital perfection stakes, but considering the film is over eighty years old it's in remarkably good condition. As for sound, in this case it consists entirely of a new orchestral score by Timothy Brock, composed especially for the film, and the digital stereo recording is perfectly adequate, if nothing spectacular. Given the relative brevity of the film, there's a generous selection of eighteen chapters.

Full marks, too, go to Image for the extras - the highlight being a superb commentary by film historian Mike Budd (who also contributes an essay printed on the DVD sleeve), which explores the film's historical and conceptual framework, as well as providing an in-depth analysis of key sequences and explaining how a film so radically experimental could emerge from a heavily commercialised German film industry. Curiously enough, the sleevenotes promise two commentary tracks, though I could only find one.

Fans of the film will also appreciate a three-and-a-half-minute fragment of the little-known Genuine (1920), a vampire story made by the same creative team immediately after Caligari, and making use of a very similar approach to the set design. Presented in the original black and white, it also appears to have been transferred at the correct speed, though sadly it ends just as it's about to get interesting ("Kill him... and bring me the proof" is the final intertitle!). As a bonus, there's also a small selection of publicity and advertising materials - reproduced in black and white at fairly low resolution, but it's a nice extra touch.

Michael Brooke