Illya goes to find Thrush's vaporizing machine, but is captured by Sophie, the headstrong daughter of the local tribal chief, Sulador. in New York Solo convinces retiring THRUSH agent David Lewin that THRUSH intends to kill him, and elicits his help. Lewin and Solo are taken to the base in the desert, just as Illya leads the band of nomads, whose confidence he has gained, in an attack on the base.

THRUSH agent Harry Pendleton is captured and commits ""suicide"" with a reversible chemical, but his superior, Simon Baldinado, refuses to revive him because he is attracted to Pendleton's girlfriend, Jojo Tyler, Solo gets Jojo to help U.N.C.L.E. retrieve the ion projection machine Baldinado has hidden at the mortuary front for THRUSH by feigning affection for Baldinado, who allows his personal plans for Jojo to affect his judgment.

Illya investigates the mysterious disappearance of cats in Soho, and he and Solo discover that a salon run by Madame De Sala is a front for her plan to develop a rejuvenation process, which De Sala plans to use on the now elderly target of her romantic desires, Sir Norman Swickert. Assisted by Joanna Sweet, a nurse, they end up in the bottom of a wine press. Meanwhile, THRUSH agent Jordin plots to obtain the process for THRUSH.

Illya investigates the mysterious disappearance of cats in Soho, and he and Solo discover that a salon run by Madame De Sala is a front for her plan to develop a rejuvenation process, which De Sala plans to use on the now elderly target of her romantic desires, Sir Norman Swickert. Assisted by Joanna Sweet, a nurse, they end up in the bottom of a wine press. Meanwhile, THRUSH agent Jordin plots to obtain the process for THRUSH.

Lucho Nostra and a group of criminals take over a tiny European country, Ingolstein, because it has no extradition treaty. Prince Frederick is afraid to kick them out, so Solo convinces princess Vicky to return and do so, only to find that she cannot because the treasury has been replaced with IOU's to Nostra for the prince's gambling debts. Nostra arranges for permanent protection by forcing a marriage between Vicky and one of his henchmen, Artie King, but the two actually do fall in love. King duels Nostra, with the fate of the country riding on the outcome.

Solo is nearly killed by a superhuman, robotlike girl, Margo Hayward, one of an army of such devices invented by Dr. Pertwee for THRUSH. Illya joins up with Margo's ex-roommate, Andy Francis, and finds the laboratory, where a roomful of robots attack them.

In spoof of ""My Fair Lady,"" Solo is recuperating from a fall into a Venice canal, Illya teams with Mark Slate to uncover Baroness Bibi de Chasseur, a THRUSH money courier who has contact with the treasurer of THRUSH. They recruit a barroom entertainer, Rosy Shlagenheimer, an exact double, to impersonate her. The switch is made, but in the confusion the Baroness makes another switch and poses as Rosy, then finds herself falling in love with Slate.

Solo and Illya go to Algiers to obtain a rare old book containing a THRUSH code from Pierrot La Mouche who has stolen it from his boss, Colonel Hamid. But La Mouche has a high price he wants U.N.C.L.E. to help him obtain Janine whom he is in love with.

Investigating the shipment of a tidal-wave machine by THRUSH, Illya ends up aboard a merchant vessel run by Captain Morton. Morton is obsessed with his past disgrace in a court martial, and the crew is on the verge of a mutiny, which Illya leads just as THRUSH arrives to take possession of the device.

Solo and Illya find that THRUSH agent Colonel Picks has developed exploding apples, which will be used to trigger a nuclear stockpile. Nina Lillette, a pretty hillbilly girl, latches onto them for excitement. Illya joins a picking crew at the farm, but he is buried alive in a tunnel with the volatile apples.

A dying UNCLE agent warns Napoleon and Illya that a group of supermen is being bred by THRUSH. The duo discover a school set up by the enemy organization in Mexico, who has already produced 7 emotionless killer students! As a graduating exercise, one is chosen to eliminate Solo and Kuryakin after they follow the boy to Austria.

In London U.N.C.L.E. agent Brian Morton (Peter Bromilow) is planning on getting married much to Waverly's disapproval. Solo and Illya help Morton on his current mission, stopping THRUSH agent Commader Kroler (Alfred Ryder) from stealing the plans for a new supersubmarine. Waverly tries to dissuade Laura Adams (Diana Van Der Vlis), Morton's fiancee, but to no avail. Morton and Laura are then kidnapped by Kroler, and Kroler threatens to kill Laura if Morton does not obtain the sub for him.