Murder out of turn

NYC cop Bill Weigand accepts an invitation to spend a weekend with the Norths at their lakeside cabin. It is the summer before the war, and the atmosphere has a faint air of "eat, drink and be merry..." until two young women are killed. There seem to be plenty of reasons for either murder, for Victim 1 is about to inherit a great deal of money, and Victim 2 is a ruthless harpy in love and business -- but what's the connection?