Ellery Queen
Insp. Richard Queen
Dr. Cazalis
Christy
Celeste
Mrs. Cazalis
Police Commissioner
Sgt. Velie
Hal Hunter
Registrar
Policeman
Lt. Summers
Miss Price
Adrian Abbott
Detective Ellery Queen has to solve a series of murders where the victims were killed in numerically descending ages, the male victims were strangled with blue cords and the female victims with pink ones.
