First published in 1880, this second novel in the "Mr. Gryce" series lays out two apparently unrelated mysteries to which Mr. Gryce assigns Q to investigate. Green introduced "Q" in The Leavenworth Case as rather a shadowy character who gets the job done in spite of, or more likely because of, his strangeness. The Strange Disappearance, this time narrated by Q, involves a sewing woman who disappears from the household of Holman Blake.