Dementia 13 (1963) review

After her wealthy husband unexpectedly dies from a heart attack in a boat (and his body is dumped), Louise (Luana Anders) fakes a note from him to his family, and then travels to his childhood home in Ireland to try to con them to changing their will so she inherits his money ... but the family still can't get over the untimely death of little Kathleen in a lake and there just so happens to be an axe murderer running around the place.  Who'd have thought that this, Coppola's first "serious" directorial effort (others were Corman-approved nudie pictures and shlock), would be a B-movie thriller influenced by Hitchcock (specifically Rebecca and Psycho): the story has nothing in it that 'stands out' (one of the family members is the killer! and has a telegraphed history of mental illness!) but it is competently composed and flows nicely (it's a slim 75 minutes long).  Most importantly: a young FFC keeps Patrick Magee under some sort of control.