Let's Kill Everybody

Meres and Gould (Henry Knowles) are interrogating East German agent Bremer (Peter Welch) in Hunter’s office. He has already confessed that someone is going to eliminate the whole Section, but before anything else can be learned, he impales himself on a paper spike. Hunter enters and is shocked to find a dead body in his office, especially one which could have provided such important information.

Hunter puts Plan D into action, in which all operatives follow and cover each other. Callan is on sick leave recovering from a minor operation to remove a cyst. He is visited by his girlfriend Jenny Lauther (Hilary Dwyer) who was his nurse in the Mander security clinic, when Hunter phones to order him in. He and Jenny take a cab, driven by Lonely, and Callan notices Gould following them, but doesn’t realise he is with the Section.

Jenny is dropped off at the flat of her new tutor, Dr. Paula Goodman (Heather Canning), who teaches history, with a strong political slant. Having lost Callan, Gould phones Hunter to report, but as he puts the phone down he is knocked unconscious by Callan. He is taken back to Callan’s flat, where Meres shows up to explain the situation. Meanwhile, Hunter is reading through some papers on all recent immigrants.

One bears the photograph of Dr. Goodman. He later gives Callan a full briefing, telling him about the O.F.F., a freelance German mercenary organisation who specialise in eliminating foreign security sections. The executioner is in London somewhere. Questioned about any contacts he has made in the last few weeks, Callan is suddenly made suspicious of Jenny.

Later in his flat, Callan questions Jenny with obvious suspicion, which upsets her greatly. However, she admits to realising that because of the nature of the clinic he was in, that he must be some sort of agent. Later, Jenny goes to see Dr. Goodman, but finds her on the phone, saying something about "Gould from intelligence. Then there’s Callan too."

With her suspicions immediately aroused, she leaves quickly, but is spotted by the tutor. Jenny informs Callan of this, but it is clear to her that he still won’t trust her, which upsets her further. Gould makes another phoned report to Hunter, but while he is on the phone, he is gassed to death by a pellet thrown into the phone box by Dr. Goodman.

At their next meeting, Dr. Goodman puts a drug in Jenny’s coffee, which only takes effect when Jenny goes on to her canoeing lesson. Jenny rapidly falls asleep in her canoe, is caught by the force of a weir, and drowns. The news is broken to Callan by an unannounced visitor to his flat; Dr. Goodman.

Hunter takes a phone call from Dr. Walker (Kenneth Gilbert), the head surgeon at the Mander Clinic, who has some information about Jenny, and agrees to go to the clinic to discuss it. Meres sees Callan, and tells him how sure they are that it was Goodman who doped Jenny. While Callan leaves to ‘take care’ of Dr. Goodman, Meres heads for the clinic to keep tabs on Hunter.

Dr. Goodman’s flat is empty when Callan arrives, and he makes a thorough search. Meanwhile, outside the Mander Clinic, Hunter’s escort, Ferguson (Stanley McGeagh) is shot dead. Hunter tries to escape, but he too is killed by the assassin. Dr. Goodman arrives back at her flat to find Callan waiting for her. They soon drop their pretence, and wait for the arrival of the executioner.

He arrives shortly; it is Dr. Walker, and Meres follows right behind. Goodman makes a lunge for her gas pellets and is shot dead by Callan. When Callan asks Meres why he isn’t with Hunter, he learns that Hunter is dead too, along with Ferguson, making three from the Section dead, to one from the O.F.F. Closing in on Walker, Callan tells him he thinks they "ought to even up the average."