With Jeff in a hospital bed with an arm and a leg in plaster, having fallen off a balcony while attempting to apprehend a safe-cracker, Marty seizes the opportunity to tell him about a spy drama that he handled alone (Jeff being out of town at the time) while he was still alive, involving a corrupt MI5 official and spy ring, the details of which he had never revealed before.
Randall is offered by a dodgy friend to take part in a money salvaging operation whereby £500,000 of old money is to be incinerated but is replaced with newspaper pieces. Not informing the police nor accepting any part in it, Randall watches from a nearby street and is caught by the police and imprisoned. Using his lady friend lawyer she tracks down his dodgy friend at his London club finding the real culprits are his lady dancers freeing Randall.
A reluctant Jeff agrees to take a valuable item worth £10,000 from Glasgow to London on the overnight express. When the consignment turns out to be an attractive blonde, Jeff initially concedes that the assignment is to his liking. How gradually becoming suspicious it turns out the blonde is a traitor involved in stealing a highly valuable postage stamp. NOTE:- Annette Andre, (Jeannie Hopkirk), does not appear in this episode.
Marty finds somebody digging around his grave. He sends Jeff to investigate the cemetery and in doing so is knocked unconscious several times by a masked 18th century axe wielder. Suspecting the gardener, Jeff accepts a job for a wealthy man in the nearby mansion and stumbles on an intricate plot to steal his insane agoraphobic son through an underground tunnel pretending to hold him to ransom. It is all part of a plot to inherit his father's fortune but when he marries his young housekeeper the plan is demised. Geoffrey Hughes appears as Harper. Also Andrew Sachs, appears in a small pre-Fawlty Towers role as the English commentator during the first leg of the international football match that Marty goes to watch.
A man enters Jeannie's life pretending that he is Marty returned from the dead. As he gradually builds Jeannie's trust with his alarming knowledge of Marty's life, Jeff, suspicious from the beginning finds that he is a runaway member of a gang and has taken Jeannie to the Cotswolds where she and Marty had their honeymoon to dig up something of the past.
In this murder mystery, Jeff is hired by a large estate manager to investigate a series of bird shootings in the manor aviary. Under the terms of the will of the manor's late owner, the estate is being held in trust for as long as the birds live (which could be twenty years or more), and will be divided up equally among the surviving relatives only when all the birds are dead. While Jeff keeps guard of the valuable birds, he discovers that members of the family of the manor are being murdered one by one, gradually narrowing down the suspects, leaving Jeff with the surprising culprit. Cyril Luckham appears as Laverick. Jane Merrow appears as Sandra Joyce.
Jeff investigates the disappearance of a wealthy young heiress's aunt. When she is then killed by a hit and run driver he is led to a medium previously visited by the aunt and uses Jeannie as a decoy to foil a thieving operation in which middle class men rob wealthy widows by murdering them in the room of the episode title, which then transpires to be a gas chamber in disguise.
Jeff is hired by a ghost hunter to investigate at a manor where the lady appears to be haunted. When the ghost hunter is murdered whilst on night watch Jeff investigates. When the man of the house is shot by his wife believing she saw a ghost, Jeff becomes suspicious and discovers that it was part of her plan to get rid of her draining husband and leave the country with her butler toyboy. Lois Maxwell appears as Kim Wentworth. Carol Cleveland appears as Laura Slade.
Jeff is hired by a company to find out who is leaking information in the stock market. Finding Jeff suspiciously out of character — and also now being unable to see him — Marty finds out that the real Jeff has been captured and that the fake Jeff is an impostor, using his status to conduct murders of financial personnel. Marty uses a hypnotist to save the day.
Jeff investigates a diamond theft in which the manager is implicated who threatens Jeff to lie about his investigation. Whilst also investigating a haunting at a country manor in turns out the diamond gang are using it as a hideout. NOTE:- Jeannie Hopkirk, (Annette Andre), does not appear in this episode.
Concerned for Jeff's mental health Jeannie sends Jeff to Dr. Conrad at the Lambert Clinic where it turns out he is the mastermind of a series of robberies of his patients using hypnotic suggestion, forcing Marty to try to find a way to break Jeff from his control before Jeff has been so severely hypnotized that he loses the ability to see Marty. David Bauer stars.