Having finally come to terms with the fact that they are sisters, Cathy and Cat are now reeling from the news that they also have a brother, Callum--and that Cathy has just snogged him.
Cat feuds with a rival delivery driver, and Cathy loses a fight with a washbasin at work; Tess' singles holiday is a disaster; Angela becomes Marilyn's houseguest from hell.
Cat and Cathy go to an adult maths GCSE course where the sexy teacher causes ructions; Tess takes a job in the worst place possible; Angela resorts to kidnapping to win back Peter.
Cathy is excited to introduce her siblings to lambing season at Auntie Dawn's farm, but Tess brings along an unwelcome visitor and Cat brings an unwise gift.
Trying to heal his rift with Angela, Callum is lured to an eventful Northern Soul Revival. The next day, their dad Colin still has surprises for his family from beyond the grave.