Borb, the president of the Balkan Republic, is visiting London to sign a military deal. His private secretary is killed by a masked wrestler, the Decapod. Steed is assigned to augment the president's bodyguards, but the wrestler continues to kill those close to Borb.

At the reading of the will of Wrightson, Steed's former batman, the man's family are shocked to discover his estate is worth a fortune. Steed and Cathy set out to find out where a twenty pounds per week draughtsman acquired such a huge amount of money, and whether it was legal.

Foreign agents are being killed, but not by British agents. Steed thinks it terribly unfair, and so does his opposite number, Nutski. They make an arrangement, and Steed and Emma find themselves with Soviet partners in an investigation of a group of very British killers.

An unfortunate motorist keeps knocking down and killing the same man: a man who's rampaging through the countryside, bulletproof and intent on destruction. A man who just happens to be identical to the urbane Professor Frank N. Stone.