John Mannering (The Baron) is called in by Scotland Yard's Superintendent Bristow to help catch the mysterious jewel thief The Shadow. No one knows the thief's identity, but he has managed to pull off many high profile robberies. However, as Mannering proceeds to track down the target, he finds the pursuer becomes the pursued.

John Creasey (September 17, 1908 - June 9, 1973) was born in Southfields, Surrey, England and died in New Hall, Bodenham, Salisbury Wiltshire, England. He was the seventh of nine children in a working class home. He became an English author of crime thrillers, published in excess of 600 books under 20+ different pseudonyms. He invented many famous characters who would appear in a whole series of novels. Probably the most famous of these is Gideon of Scotland Yard, the basis for the television program Gideon's Way but others include Department Z, Dr. Palfrey, The Toff, Inspector Roger West, and The Baron (which was also made into a television series). In 1962, Creasey won an Edgar Award for Best Novel, from the Mystery Writers of America, for Gideon's Fire, written under the pen name J. J. Marric. And in 1969 he was given the MWA's highest honor, the Grand Master Award.