Four Sided Triangle is a 1953 British science-fiction film directed by Terence Fisher, adapted from the 1949 novel by William F. Temple. It stars Stephen Murray, Barbara Payton and James Hayter. It was produced by Hammer Film Productions at Bray Studios.
The film deals with the moral and scientific themes that were soon to put Hammer Films on the map with the same director's The Curse of Frankenstein. Four Sided Triangle has most in common with Fisher's Frankenstein Created Woman.