When Boston Blackie performs magic tricks at a Thanksgiving Day party for the inmates of a women's prison, Dinah Moran (Constance Dowling) volunteers to enter a booth.

A trip to the library reveals that Dinah was sent to prison for three years for a robbery that netted $100,000 (which was never recovered) and a dead victim.

In the meantime, Blackie's friend returns home from a trip early and finds Jani's body in the closet.

When Farraday and his dimwitted assistant, Sergeant Matthews (Frank Sully), arrive, Blackie tells them he recorded Irene's confession when he turned on the radio for some music.

Blackie then informs Farraday that there was no recording; he merely used ventriloquism to reenact his part of the prior conversation to fool Irene.