When 'Lady' Sandra Abbott (Academy Award® nominee, Imelda Staunton) discovers that her husband of forty years is having an affair with her best friend, she seeks refuge in London with her estranged, older sister, Bif (Celia Imrie). The two could not be more different - Sandra is a fish out of water next to her outspoken, serial dating, free-spirited sibling. But different is just what Sandra needs at the moment, and she reluctantly lets Bif drag her along to a community dance class, where she starts finding her feet.