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.
Sidney Blackmer
as Police Commissioner Thatcher Colt
Rick Vallin
as Anthony 'Tony' Abbot (as Ricki Vallin)
Byron Foulger
as Everett P. Digberry
Herbert Rawlinson
as District Attorney Bill Dougherty
Lynn Starr
as Miss Spencer
Barry Bernard
as Capt. Edgar Walters / Frank Galloway
Trude Rosen
as Nina Politza
Thornton Edwards
as Enrico Lombardi
John Ince
as Police Captain Mike Flynn
Martin Ashe
as Officer Murphy
Walter James
as Police Captain Tom Henry
Frank Darien
as Samuel Wilkins
