sisters of death (1976)

aka Death Trap. Death time House.
"Smart chick."
An initiation into a sorority goes wrong, when one of the initiates dies. Seven years later those involved come together again, at what turns out to be the estate of the father of the dead girl...
The sort of film where young and dumb women do things like take showers or nosy around empty parts of a house, when they know a serial killer is stalking them. In other words, infuriating!