When Olivia's mother dies, she leaves behind an apology Olivia could never have expected. Years ago, Maggie did everything in her power to end a love affair between the teenage Olivia and her stepbrother-to-be Richie. Now, over twenty years later, Olivia has a letter that contains his address - and her mother's blessing to seek him out. 'Follow your heart,' Maggie writes, 'and put right my mistake.' It sounds like nothing more than a dying woman's fantasy; certainly not an instruction for a grown woman with a husband she loves, two sons in their teens and an established life in the same London suburb she grew up in herself. This is where Olivia belongs, isn't it? But, tormented by the memories her mother's letter stirs, she makes the decision to travel to the small coastal town where Richie lives with his young daughter Wren. Rediscovering her first love and falling for him a second time, Olivia realises that this is the life she had always imagined for herself, the one she has wanted all along. But where does that put the family she has left behind?