What Became of Jack and Jill? is a 1972 British horror film directed by Bill Bain and starring Mona Washbourne, Paul Nicholas, and Vanessa Howard. It was part of an abandoned attempt by Amicus Pictures to compete with Hammer Studios by breaking into the grindhouse market. Studio executives were ultimately too disturbed by the final product to release it under the Amicus name, and they sold the film to 20th Century Fox.