Four-Sided Triangle

Barbara Payton - Lena/Helen
James Hayter - Dr. Harvey
Stephen Murray - Bill
John Van Eyssen - Robin
Percy Marmont - Sir Walter

Four-Sided Triangle became Hammer's first venture into fantasy and science fiction, although its idea of duplicating a woman to make up for the loss of the original had already been tried in Stolen Face. Here the scientific aspects were emphasised to such a degree that, as with many other science-fiction pictures, these became the main point of appeal and "name" stars could be largely dispensed with, allowing the money to be invested in sets and laboratory paraphernalia.

Two scientists working in a barn in a remote village both fall in love with the same girl, Lena (Barbara Payton), who has recently returned to her hometown after ten years in America. She elects to marry one, Robin (John Van Eyssen), leaving the other, Bill (Stephen Murray), to overcome his grief by perfecting a machine to duplicate her exactly. Such is his success that he names his creation Helen, but the replica also prefers his romantic rival! Ultimately creator and creation perish in one of those fires that have proved such a handy way of clearing up the plot and making life on this planet safe from the errors of science.