The warning of a dying man tips Steed off that ecologist Rydercroft is to be killed at noon. All plans are taken to protect the man's aircraft but it still crashes. Soon the Avengers come up against a new breed of enemy.

In an attempt to break Steed's perfect shooting-range record, Purdey tackles the range with all her grace and skill. However, it's not enough as she misses one tiny percentage and gets hit with a mark. But other agents begin to die who have performed similarly, and Steed and Gambit start putting the clues together and find that they must work fast to save their friend and colleague before she succumbs to a nasty poison.

A bizarre series of deaths of high-ups in the government becomes the business of Steed and his colleagues when a personal friend of his becomes one of the deceased. However, due to suspicion from the delicate nature of the case...apparently people are being duplicated by an unscrupulous firm...Steed, Purdey, and Gambit all go off on their own and make individual progress into the case. However, it seems that the situation is too far-reaching and confusing for each alone. They must work together and figure out quickly, who's who and what's what, before they themselves become the next targets.

2 scientists are developing a new growth drug which could end world famine. Unfortunately some of the drug has been flushed down the sink resulting in something nasty in the sewers.

Steed's plan to have 3 memory experts memorise a third of each of the Allied defence plans for courier purposes seems to have been a perfect success until Juvenator arrives with a machine capable of draining minds.

Mason is the paymaster to a group of informants, but all is not what it seems: the informants are a single man. When Mason suspects this, he is murdered by Wallace, who has been lining his own pockets. Steed begins to investigate, and Wallace decides that the only option left is to frame Steed and kill him.

Agent X41 (codename ""Scapina"") is the USSR's most effective spy. But a photograph has fallen into the hands of the Avengers which may give a clue to his identity. The trail leads the trio to Toronto.

April 1969: Typhoon Agatha rages causing a new piece of coastline suddenly to appear in Toronto. It's up to the New Avengers to uncover the truth behind it all.

The trio are on the trail of a mysterious agent ""The Fox."" Although he escapes, he leaves a palm print on the roof of a car owned by the aged Miss Daly and the Avengers must preserve the print to make a positive ID on their target.