Why do a sleazy antique dealer and a wealthy collector suddenly become interested in 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 discovers that it might be a priceless artifact. Thieves follow her to Chicago and to the home of a blind woman in Riverside, who also owns one of the goblets. The exciting climax takes place on the steps of the Art Institute of Chicago between the roaring lions.