Hunter’s archenemy, a Soviet agent and killer known as Bluebird, is suspected of killing an American who betrayed the Soviets after leaking American nuclear secrets to them. Bluebird murders a success…

A Soviet double of Hunter—created through the use of plastic surgery—arrives to carry out a plot to kill General Baker and frame Hunter for the murder. But first he has to fool Marty into believing th…

A mad scientist programs an American agent to kill Hunter. He then arranges for Marty to have a car accident so that he can treat her for her injuries and uses the opportunity to program her to kill h…

After a hitman dies during a car chase, Hunter switches wallets with him, takes his place, and sets out to find out who hired the hitman and who the hitman's target was—and soon begins to realize that…

After a witness for a United States Senate committee investigating a connection between organized crime and a U.S. government intelligence agency (the fictional "GIA") is murdered, Hunter and Marty fa…

In a flashback to before Hunter′s 1969 resignation from "the Agency" when he was still their chief of operations in West Berlin, Hunter becomes a wary ally of an East German spy who shot his fiancé to…

Another flashback to the time when Hunter was still with "the Agency" as its chief of operations in West Berlin before he resigned in 1969. When Hunter, Marty, and Baker try to stop renegade American …

Dr. Martin Reed, a chemist working for the U.S. government, disappears mysteriously. At the same time, Dr. William Maklin, one of his associates, is killed in a plane crash. Investigating Maklin's dea…

When Hunter helps with the exchange of a U.S.-held Communist spy for a Communist-held American spy—who happens also to be his favorite instructor in spycraft—persons unknown intervene in the exchange …