I really liked this one, but I thought "Mother" was a a man (named "Mother"). I thought this was a take-off on Psycho and since old radio plays usually portray homosexuals as psychopaths, that "Mother" was one of those. I'd better listen more carefully!
George, she was probably reading the script for the second time. These were produced in a day at CBS New York. The Wiki article on CBS Mystery Theatre is enlightening.