At the heart of Dover's Market Square lies the Castle's Café. A bustling, homely place run by the formidable Nellie Castle and her six children. Since the scandalous birth of her beloved son 10 years before, Marianne, Nellie's eldest daughter, has preferred to stay in the kitchen, hidden away from the town gossips. Overcome with shame, Marianne has never revealed the name of Donny's father - not even to her own mother. But with World War II just around the corner, Marianne's past catches up with her. And suddenly the lives of the Castle family become a lot more complicated.

As the Battle of Britain rages, the Castle family are standing their ground at the heart of the community, running Castle's Café. German guns shell Dover and danger lurks around every corner, but despite this, Lily Castle is excited to be starting her nursing career at last. Lily is enjoying her life. She's a good nurse, has a group of friends at the hospital and there is romance on the horizon. That is until her world comes crashing down around her. When she tries to help an injured prisoner of war at the hospital, she ends up implicated in a crime.