When a Mini containing a radioactive isotope is stolen from outside the Aidensfield Arms, Mike and the team are under pressure to find it as soon as possible to stop it from falling into the wrong hands. Luckily, Mike finds the car. But the isotope has gone... Meanwhile, Greengrass is summoned by a mysterious messenger, who turns out to be his estranged brother Cyril. Unhappy to see his sibling, Greengrass soon has a change of heart when Cyril offers him partnership in a dog racing business. Elsewhere, Aunt Mary settles into life in Aidensfield, with a little help from Blaketon, while Bellamy's love life is nom-existent now that he has moved in with his gran, and troublesome duo Trevor and Stuart are up to their old tricks in the village.