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