When James McElroy saw the ad for a lodger with 'Bibi Sanders' in a smart Edinburgh street, he pictured a glamorous young landlady with whom he would form a meaningful and deep relationship. But Bibi's in her seventies. She's led a full life, including marriage to the domineering and difficult Callum, now deceased, and raised six children. She's not sure what to make of James and suspects - rightly - a troubling secret in his past. When Bibi sets out to re-visit the past for the final time via a tour of Britain in her rather unexpected Volvo sports car, James decides to go with her. It's a journey full of surprises and revelations which will change them both.