Guest Stars Tallulah Fox as Sarah Beatty Fifi Fox as Sarah Beatty Kirsten Foster as WTC Stapleton Tuppence Middleton as Vicki Walmsley Sanjeev Bhaskar as Kanan Dutta Catherine Steadman as Polly Beatty Neil Stuke as Professor Andrew Crane Emily Joyce as Jane Grace Hermione Gulliford as Lucy Sopher Dominic Mafham as Frank McLean Lesley Vickerage as Katherine Dutta Adam Wadsworth as Joshua Grace Beatie Edney as Justine Skinner