Wealthy industrialist Frederick Haley, who has been appointed to an important position at a humanitarian foundation, asks Checkmate to find out who has been threatening his mistress, whom he plans to marry after leaving his wife.
Checkmate is hired by a woman to protect her husband, Stephen Jordan, who publishes a newspaper opposed to a referendum on legalized gambling in the city of Midvale. He has been receiving death threats and, thanks to Dr. Hyatt, survived an attempt to kill him by poisoning. The culprit at first is thought to be a supporter of the referendum, but there may be something in Jordan's past that could shed light on a different motive.moreless
The Checkmate team is in Chinatown on behalf of a colleague of Dr. Hyatt's, a Dr. James Low, who claims his Chinese wife may try to kill a man who is supposedly blackmailing her in an attempt to ingratiate himself into Chinese society. Their investigation reveals that they are being used as pawns in an elaborate web of deceit, greed, and possibly murder.moreless
A woman who runs a home for struggling artists has been receiving death threats, and suspicion falls on her boarders, including a pretty young poet who is the object of Jed's affections.
Checkmate is hired to protect rodeo star Len Kobalsky from his girlfriend Marcy Lowell's brother, who disapproves of their relationship and prefers she marry someone from a wealthy family such as theirs. As it turns out, the real threat to Len is from one of his fellow rodeo riders.
Checkmate is hired to protect the life of Judge Leland McIntyre, who is conducting a series of lectures concerning a trial over which he presided eight years ago resulting in him sending a man to the gas chamber. Checkmate suspects that one of the students may be connected to the case and signed up for the course to get to him. In the course of their investigation, the judge begins to question his own conduct in the trial.moreless
Two convicts, both former Catholic schoolboys, escape by shooting a policeman, then hole up in a monastery while Dr. Hyatt is visiting and hold the Father Abbot and Dr. Hyatt hostage. Dr. Hyatt appeals to the penitential instincts of one of the men in an effort to end the situation.
Jed and Dr. Hyatt go undercover as members of a hobo community to protect a man known as Doc, acknowledged leader of the community. Years ago Doc was disinherited by his wealthy father for behaving irresponsibly with money, but now his dying father wants him back, and others in his family want him dead so they won't have to pay him an allowance. When Doc winds up inheriting the entire estate, he goes to town with it, making Checkmate's job more difficult.moreless
Karen Vale, who served five years for acting as a courier for enemy agents, is staying at a halfway house for women run by a senator's widow, Mrs. Creighton, and faces the hostility of her fellow citizens and from protesters outside the house. Mrs. Creighton hires Checkmate to protect her. In the course of their services, the Checkmate team finds Karen's greatest threat is from her former comrades who have infiltrated the protesters and even the house itself to try and bring her back into their circle, or eliminate her.moreless
Victor Ragar, a cellist at a music conservatory that fronts for an Eastern Bloc freedom movement of which he is the leader, is in danger of being assassinated by a compatriot who accuses him of betraying the cause. The would-be assassin, Paul Delorio, also has a personal motive- Victor ran off with Paul's wife while Paul was in prison in the old country. The conservatory's director, also a member of the movement, hires Checkmate to protect Victor.moreless
Eddie Phillips is a gifted but troubled young art student with an anger management problem. After being informed of his father's arrest on embezzlement charges, he attacks Dr. Hyatt and is put on a year's probation. Laura Hammond, an art teacher, takes an interest in Eddie and tries to help him with his anger problem by encouraging his painting, but must take care he doesn't misunderstand their relationship.moreless
Checkmate is called to investigate the disappearance of an employee at Venus West, a beauty farm for women. Don finds himself falling for the beauty center's manager, who is not all she seems.
Jed poses as a publicity man on a movie set to keep a close watch on suicidal actress Vicky Page, accused of trying to kill another actress who she suspects is having an affair with her boyfriend, director Ernie Chapin.
In a mostly comedic episode, Jack Benny guest stars as Jack Bowen, a beloved TV comedian much like Benny himself, who is serving as the Grand Marshal of the Pioneer Bowl Parade and football game. Also in town for the big game is the Checkmate team, and while there they end up mixing business with pleasure after Jack becomes the apparent target of a would-be assassin.moreless
An amnesiac woman is taken home from the hospital by a man claiming to be her husband, but the woman doesn't believe that she could be his wife, and despite her memory lapse believes she has reason to fear for her life. Checkmate investigates.
Highly successful construction engineer Howard Gentry calls on Checkmate after an apparent attempt on his life. Checkmate suspects his identical twin brother Robert, but Howard does everything he can to dissuade them of that suspicion. His reasons for doing so lead to an intriguing conclusion.
Zoe Kamens is an artist who just wants to paint honestly by copying masterpieces, but her husband, a man of questionable ethics, has been pressuring her to make copies and pass them off as originals. He in turn is being pressured by a crooked art dealer. Zoe turns to Checkmate, but keeps changing her story because of her shifting feelings for her husband, and complicating matters is the fact that she and Don were once an item, something Don has trouble forgetting.moreless
Sid Caesar appears as Johnny Wilder, a highly popular but guilt-ridden, somewhat neurotic San Francisco disk jockey who believes that a former rival whose own career went on the skids blames Johnny and wants to kill him. The station's owner hires Checkmate to protect Johnny- maybe from himself.
Jocko, a man whom Dr. Hyatt recommended be remanded to a psychiatric facility for treatment at his parole hearing five years earlier, still holds a grudge, believing that Hyatt wanted him confined for life as a psychopath. On his birthday, Hyatt gets a surprise visit from Jocko, who holds him at gunpoint with the intention of forcing him to concoct nitro for deadly use.moreless
Luther Gage, an egomaniacal, methodical killer whom Dr. Hyatt helped send to prison, vows revenge and conducts a plot planned to the last detail to carry it out. Checkmate employs the services of Chris Devlin, seen here for the first time, to enter the prison posing as a new inmate to figure out and thwart Gage's plan.moreless
A fictional state governor running for re-election stages a phony assassination attempt to boost his chances for victory, and hires Checkmate, ostensibly for protection, but in reality to provide an appearance of credibility. The governor's son is vocal in opposing his father's tactics, but dutifully goes along, mindful of a future political career of his own. Meanwhile, as the campaign winds down, a real threat to the governor's life emerges from within his own campaign.moreless