Hell's Gate (1970)

A beautiful-but-loony tunes insane asylum inmate thinks she's the reincarnated soul mate of a deranged 19th century serial killer who happens to live in modern times in the guise of her psychiatrist -- how handy. Agnes Thatcher (Patsy Kensit) uses her extraordinary sensuality -- not to mention her ruthless bloodthirstiness -- to break free in a bloody spree to find Dr. Campbell (Patrick Muldoon) when the doctor leaves for a quiet seaside vacation with his wife (Amy Locane) and young daughter.