1986. Cathy Simpson is a single mother with a young son, Jason, living in a flat in Conway Place, north London. Desperate to provide her boy with a father figure, she joins a dating agency and meets the charming and attentive Simon Scott, who forms a strong bond with Jason. Although Simon and Cathy marry she can never forget the man who was Jason’s father. Cathy’s best friend, Holly, takes it upon herself to discover his whereabouts, a task which has unexpected consequences for everyone.