Episode trailers from 'The Radio Times' Part 1. A fisherman who knows more than he’s telling, men with binoculars and a fast American car; and waiting out at sea a man with a high powered rifle. Part 2. John’s father has disappeared and the police don’t seem interested. John and Susan decide to solve the mystery for themselves but they don’t know that someone is watching them all the time. Part 3. John catches sight of his father again, with three other men, he also sees the police in pursuit. The chase is on !... Part 4. Hot on the trail, John and Susan have no way of knowing that the motorcyclist just behind them is one of the gang... Part 5. John and Susan are trapped. Can they find a way out ? Part 6. John and Susan may think they have escaped but the man with the motorbike is waiting... Part 7. Just when John and Susan’s situation seems hopeless, a jet-boat speeds out across the lake... Part 8. A mountain in Cumberland; the tables are turned on the motorcyclist, but what will John and Susan tell the police ? Part 9. When John overhears his father talking to Selby it sounds as though he’s joined the gang after all... Part 10. Yorkshire. John gets himself into a desperate situation and Susan is alone in a car she cannot drive ! Part 11. Kessler and Bowers are in Edinburgh. John and Susan don’t know why, but they do know that something is going to happen very soon – during the Military Tattoo. Part 12. As Kessler presses the trigger a plan goes into operation worth half a million pounds, and John and Susan seem powerless to stop it... Part 13. A quiet Scottish cove; a fast Cruiser; a fake ambulance...and a race against time...