Thy arm alone

Betty Shapley was a local beauty, for whose charms three young men fell heavily. But her coquetry would lead to death for one of her admirers, Herbert Pollitt; a fugitive's life for another, Vincent Gray; and becoming a murder-case witness for the third, Tom Clayton. Inspector Morgan and Sergeant Claythorne investigate the death, and suspect Vincent Grey. So Betty, former pupil of Roseway College for Young Ladies, asks Maria Black--the headmistress detective--to prove Grey's innocence.