Sophie Petzal Creator, Screenwriter, Executive Producer Anna Maxwell Martin Theresa Actor Rachael Stirling Helen Actor Rhashan Stone Fraser Actor Peter McDonald David Actor Ken Nwosu Eddie Actor Amelie Bea Smith Eva Actor Fraser Holmes Ben Actor Jonas Armstrong Gareth Actor Jim Howick DS Robin Parks Actor Jodie McNee Jean Actor Tia May Watts Georgina Actor Julie Barclay Ana Actor Kate Morgan-Jones Dr Juliet Rose Actor Tony Leader Leslie Saunt Actor Dan Burgess Jeremy Actor Elèna Gyasi Stephanie Greenford Actor Carolina Giammetta Director Catrin Lewis Defis Producer Sarah Warne Music, Original Music Jonathan Fisher Executive Producer