Twins of Evil is without doubt one of Hammer's very finest films. The film blends together a few different elements of horror. We've got witches (and the resulting witch hunts), devil worship and, of course, vampirism. These things combine to make one very nice Hammer film indeed. Naturally, the film benefits immensely from the incredibly beautiful ladies that play the twins of the title - Mary and Madeleine Collinson. The two are the ultimate in sweetness, which makes it all the better when one of them becomes more like the title suggests. The plot is relatively simple given all the elements it combines. We follow Gustav Weil (Peter Cushing on fine form) as a religious man by day, and witch hunter/burner by night. The beautiful twins of the title go to live with him after the death of their parents. However, the village in which they live is beneath a castle, inside of which lives the evil devil worshipper; Count Karnstein.
Like some Hammer offerings, Twins of Evil does cross the line into camp here and there and features a number of over the top performances but that being said Hammer Horror is at their best when they're combining several things and tweaking classic stories, and that is what is done here. Twins of Evil is a very original take on the classic vampire story and is therefore a lot of fun to view. It benefits from the direction of John Hough; the man who would later go on to make the seminal classic, "The Legend of Hell House". I actually think he did a better job here than he did there. For Twins of Evil, Hough has captured a foreboding and creepy atmosphere, through use of lots of smoke and a Gothic period setting that involves such favorite horror locations as graveyards and old castles. Hough has also given the film a very heavy handed score, which although gets a little silly, increases the camp value of the film and is therefore beneficial to the film.
Like many a great horror film, this one benefits from a great finale, which includes numerous gory sequences including, most notably, a decapitation scene; which gorehounds are bound to find satisfying. I'm a big fan of Hammer horror, and I would certainly place this one among their top five best achievements. Highly recommended viewing