When "Lady" Sandra Abbott (Imelda Staunton) discovers that her husband for over 40 years has been having an affair with her best friend, she seeks solace in her estranged and bohemian older sister Bif (Celia Imrie). The two sisters could not be more different from each other: while Bif has no problem in finding men to go to bed with, Sandra is still reluctant to break up with her previous life. Slowly, both will end up needing each other because, after all, the one is the perfect complement for the other.

The film is directed by Richard Loncraine, who also directed '5 Flights Up'. David Hayman, Joanna Lumley, Timothy Spall, Indra Ové, John Sessions, Richard Hope and Josie Lawrence complete the cast.