The Panther’s Claw

The police arrest a man climbing over the wall of a cemetery after midnight. He claims that he is being blackmailed and is following instructions he received by mail to leave $1000 on a certain grave. It turns out that he’s not the only one who got a blackmail letter from the same person–calling himself “The Black Panther”–and it also turns out that all the recipients are connected to an opera company.