Steed investigates the death of a colleague while Gambit witnesses the kidnapping of Professor Von Claus. Purdey scuba dives to the remote island of St. Dorca, where a monastery hides a secret and Germany's greatest treasure.
Steed, Purdey and Gambit, aided by a flock of rabid female fans rescue defector Professor Vasil from under the nose of Ivan Perov at an airport. Perov reactivates a group of 13 sleepers known as the House of Cards in order to avenge himself on the Avengers and get Vasil back to Russia.
Double agent Felix Kane is horribly disfigured while being chased by the New Avengers. A year later, Kane forces Frank Goff to breathe new life into old Cybermen left in storage by Goff's former employer, Dr. Armstrong. Further more, Professor Mason is kidnapped and forced to apply the Cybernaut technology to rebuild Kane's body so he can exact his revenge on Steed, Purdey and Gambit personally.
Professor Turner has found the ultimate carrier for a host of deadly diseases, calls him Midas and offers him to the highest bidder in exchange for gold. However, Steed's former colleague Freddie, now a vagrant is on to him and manages to pass over a few hints to the New Avengers before he succumbs to everything.
Ministry agents are dropping dead of natural causes either on leave, or just about to go. Discovering a pattern, all clues lead back to the training range where Purdey has just scored a 99% walk through. Unfortunately for her, it's the one remaining per cent that kills.
D16 Agent Irwin Gunner was on the trail of a double agents known as White Rat in 1960 when an arranged trapeze accident caused him to suffer amnesia. 17 years later he begins to regain his memory and vows to track down the Rat, who has certainly moved up in the world by now. As Steed, Purdey and Gambit race to catch up with the long lost agent known only to them as 'Flyer', the White Rat ans his accomplices do the same in order to silence him.
The New Avengers uncover an operation that is substituting doubles for politicians and other high ranking members of society. All the lookalikes seem to have been found amongst the drunks and derelicts of The Mission for the Distressed and Needy, so Gambit pretends to be a drunk named Walton, while Purdey infiltrates the organization on her own as 'Lollita'. Meanwhile, is Steed still himself, or is there a replacement in his stead?
The New Avengers are present at a demonstration of a new gas, S-95, that can knock out people instantaneously. Unfortunately a criminal called Brady is also present, steals 2 cannisters as well as the anti-dote and puts the heart of London to sleep the next morning. Now Steed, Gambit and Purdey are the only people left awake and able to stop the criminal gang from robbing all the banks of London. Unfortunately, Steed & Gambit have no way of contacting Purdey, and Purdey has trouble keeping her pajama bottoms up.
Steed has invented a way of using a triumvirate of agents with photographic memories to memorize top secret information in three parts. Each third being useless without the other two. A brilliant criminal named Juventor plans to use a mind-swapping device to piece all three parts together and sell the combined information to the highest bidder. When he learns The New Avengers are closing in on him, Juventor decides to swap brains completely with one of his victims.
General Stevens has gone missing while inspecting the 19th Special Commando Division unannounced. Gambit intercepts a canister of combat footage starring the commanding officer of the 19th: Colonel 'Mad Jack' Miller. Purdey has her finds her way into the training area by way of a pub filled with soldiers.
Scientists Thornton & Carter have discovered a radioactive isotope that causes vegetables and living things to grow exceedingly. Rather than informing the Ministry, they decide to keep the secret for themselves. But when some of the isotope is spilled down the drain, reports soon surface of a monster emerging from the sewers intend on killing man.