Alan Buttershaw and Celia Dawson, both in their seventies and widowed, reunite after putting their profiles on a popular social-networking site. The two discover they still feel as passionately for each other as they did nearly 60 years ago.
Celia and Alan buy an extravagant sports car instead of an engagement ring, and throw an engagement party at the farm which descends into chaos for both families.
Celia and Alan's search for a wedding venue leaves them trapped in a haunted medieval mansion. Caroline and John fight in the garden, while Raff moves out of the farm and Paul moves in.
Caroline and Gillian surprisingly become close when Alan and Celia go missing for a night. Robbie helps find the pair and John discovers that Caroline has been seeing someone else.
Alan finds it difficult to choose his best man. Meanwhile, Caroline and Gillian discover they were born on the same day, but their respective birthday celebrations descend into chaos when John outs Caroline and Kate.
John's revelation that Caroline is gay isn't handled well by Celia. She is extremely rude to Kate during a dinner with Alan and Caroline. Alan is shocked and saddened, declaring he will call off the wedding with Celia.
Derek Jacobi
Alan
Anne Reid
Celia
Sarah Lancashire
Caroline
Nicola Walker
Gillian
Josh Bolt
Raff