The Manster (双頭の殺人鬼, Sôtô no Satsujinki) is an American tokusatsu, a 1959 horror film shot entirely in Japan with Japanese talent behind the camera, and starring British actors Peter Dyneley and Jane Hylton. The film was notable for its creative use of special effects. The film is also known as The Split in the United Kingdom, Doktor Satan in Greece, and sometimes informally referred to as The Two-Headed Monster.