

Diabolique

The wife and mistress of a cruel school master collaborate in a carefully planned and executed scheme to murder him. The plan goes well until the body, which has been strategically dumped, disappears. The psychological strain starts to weigh on the two women when a retired police investigator begins looking into the man's disappearance on a whim.
I watched the Dr Sapirstein Alternate cut. A much tighter story in the vein of the original and converted to black & white. it really works. Try and track down a copy.