Mike and Jackie's wedding day takes a dramatic turn when he and Bellamy work alongside CID to track down two train robbers. Meanwhile, Greengrass receives a shock when he is reunited with his eccentric sister Bella, whom he has not seen for 22 years. She immediately begins ruling the roost at his cottage, leading to him taking up residency in a caravan on the moors.

After a suitors is raided, it has unexpected consequences for Mike's marriage when he makes a shocking discovery about Jackie whilst investigating the incident and is given reason to believe his new wife is having an affair. Meanwhile, Greengrass is saddened when his old friend Cylis dies and offers to help his wife Agnes organise the funeral. Trouble arises when Greengrass discovers Cylis donated his body to medical science without telling his loved ones. Always the optimist and trying to spare the feelings of a widow, Greengrass comes up with a masterplan to overcome this new problem, much to Bernie's dismay.