Milly and Jess have been best friends forever. They've shared everything since they were kids - secrets, clothes, laughs, substances, boyfriends... now they are trying to be grown-ups. Milly has a high-flying job and lives in a beautiful townhouse with husband Kit and their two kids. Jess is a town planner and she and her boyfriend Jago live on a bohemian houseboat on a London canal. Their friendship is as rock solid as ever. That is until Jess struggles to have a much longed-for baby and Milly finds out she has breast cancer. How do you share that?