Ken is asked to investigate the fiancée of Lawrence Varlish. He suspects that she might be having an affair with her hypnotherapist, Geoffrey Phillips. Harry goes to see Phillips, posing as an anxious patient, and soon discovers that Varlish is worrying over nothing. Two suspicious-looking South African men are waiting in the car park of the newly-opened CBS offices. They are anxious to collect something from a boat on the river. Nearby a narrow-boat belonging to a certain Mrs Walters is commandeered at gunpoint by Hobson, a suave man with a painfully cultured accent, accompanied by a Scotsman called Dilkes. They urgently need transport because their own boat has broken down. That night, when Ken is asleep on his yacht, he is woken up by the sound of heavy objects being thrown in to the water. Still half asleep, he peers out of the window but can't see anything and soon goes back to sleep. After advertising in the local paper, Ken and Harry are inundated with enquiries for missing pers