The Peril of the Rails

Unhappily married Richard Mason concocts a meticulous scheme to kill his shrewish wife so that he'll be free to marry her sister.

Federal agent Alexandra Barnes believes that Catherine Petersen is a serial killer who marries rich men and then murders them for their money. But since Catherine is seemingly a master of disguise and has multiple identities, Alexandra can't prove anything with conventional detective work. With no other option, she goes undercover, pursuing the same man as Catherine, and hoping that Catherine will slip up and reveal her true identity.

Young socialite Iris Carr befriends an older woman while traveling solo by train. When Iris wakes from a nap, the woman is gone and other passengers claim she never existed.

P.C. George Dixon is a long-serving traditional copper who is due to retire shortly. He takes a new recruit under his aegis and introduces him to the easy-going night beat. Dixon is a classic ordinary hero but also anachronistic, unprepared and unable to answer the violence of the 1950s.

In New York City, an insolent pickpocket, Skip McCoy, inadvertently sets off a chain of events when he targets ex-prostitute Candy and steals her wallet. Unaware that she has been making deliveries of highly classified information to the communists, Candy, who has been trailed by FBI agents for months in hopes of nabbing the spy ringleader, is sent by her ex-boyfriend, Joey, to find Skip and retrieve the valuable microfilm he now holds.