Book: Beast in View by Margaret Millar (1956) Random House

This is a tightly woven psychological thriller that surprises all the way to the last sentence.

There is a limited cast and limited locations, which lent itself to becoming an episode of the Alfred Hitchcock Hour..  This book got the Edgar Award in 1956 and is considered on of the 100 best mystery novels of all time.

Mrs. Millar is an excellent craftswoman and all of her fiction is worth reading.