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 farmgirl 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 others' lives as they manage through the posh world of Berkeley Square.