Why do a sleazy antique dealer and a wealthy collector suddenly become interested inh an unknown artist named Jo Allison? Is it the mysterious goblet she used in three still life paintings?
Jo's apartment is burglarized and she is followed and threatened. When she attempts to determine the provenance of the goblet, she discover it might be a priceless artifact.
Thieves follow her to Chicago and to the home of a blind woman in Riverside, who also owns a similar goblet.
The exciting climax takes place on the steps of the Art Institute of Chicago between the roaring lion.