The Kenken Killings

When the late Chester T. Markowitz, a man she never met, leaves $10,000 to his beloved wife, Cora Felton, the Puzzle Lady can't help cashing the check. Then Cora's least favorite ex-husband, Melvin, shows up with an attorney, demanding that her alimony be terminated on the grounds that she remarried. When a key witness in the alimony hearing is murdered, a KenKen puzzle is left at the scene. Is someone trying to tell Cora something?