The Other Side of the Underneath (1972)

The Other Side of the Underneath is a 1972 British feature film written and directed by Jane Arden and starring Sheila Allen, Liz Danciger, Penny Slinger, Ann Lynn, and Suzanka Fraey. Other members of the Holocaust Theatre Company appear in the film. It is the only British feature film in the 1970s to be solely directed by a woman. Jane Arden herself also appears in the film. The title of the film is taken from a line in Arden's play Vagina Rex and the Gas Oven which was a huge success at the London Arts Lab in 1969.

More at Wikipedia.