This one was a bit tough. The best I
could come up with was The
Curse of the Demon (1958, 83m, Columbia) which
starred Dana Andrews as a "Stuffy cynical psychologist
who doesn't believe that a series of deaths of been caused by
an ancient curse". One of his co-stars was 70, so she
may have qualified as a "prune". Based of Montguae
R. James book Casting the Runes