A woman returns from her honeymoon and then finds her husband murdered. When she seeks help from the sister she lives with, the sister tells her she has no husband, was never on a honeymoon, and that she is having another one of her spells.

Sister and 'husband' are manipulating things to make her think she is insane so they can commit her an claim her part of their father's considerable estate.

The involvement of a Columbo-type policeman keeps the plot moving.