Berkeley Square is a warm-hearted family drama set in turn-of-the-century London, where three young girls come together as nannies and grow to be friends. Matty is a tough East End girl who has worked her way up the domestic ladder of London society's finest families. Spirited Hannah flees to London with her child after falling disastrously in love with the eldest son of a grand Yorkshire family. Generous, yet naive, farm-girl Lydia becomes a nanny in a forward-thinking family light years from her own. Over the course of time, the three young nannies become enmeshed in each other's lives as they manage through the unpredictable twists and turns of love, happiness and secrets in the posh world of Berkeley Square.