The Indian Scarf (1963)

When a wealthy man dies, his avaricious relatives look forward to inheriting all his money. However, he leaves a provision in his will that they all must spend a week together in his castle before they will be able to inherit anything. At the castle (which is cut off from the outside world), the relatives soon begin to be killed off one by one, each strangled with an Indian scarf. The estate's executor, a lawyer, sets out to find the killer before everyone--including himself--is murdered.