Guest Stars Fiona Dolman as Sarah Barnaby Claire Skinner as Kitty Oswood Nicholas Gleaves as Ray Fryer Jodie Tyack as Polly Oswood Samuel West as James Oswood Anamaria Marinca as Petra Antonescu Georgie Glen as Mary Oswood Abigail Cruttenden as Nell Fryer John Macmillan as Solomon Franks Susie Blake as Gemma Christie Chris Lew Kum Hoi as Ronin Chow Karl Theobald as Doug Vaughan Paul Shelley as Walter Oswood Lotte Spring Rice as Samantha Berry Thalissa Teixeira as Jane Everard