Guest Stars Hannah Arterton as DC Ally Caine Geraldine James as Julie Wells Michael Maloney as Alan Wells Don Warrington as Ray Kenwood Sophia La Porta as Britnay Shearer Kim Allen as Jane Shilling Lauren Douglin as Izzy Allan Aedan Duckworth as Young Mark Saoirse-Monica Jackson as Sasha Lara Bradban as Blonde Dylan Jupp as Simon Marshall Leon Ward as Andy Megan Bradley as Young Pru Niall Greig Fulton as Richard Payne Charles De'Ath as Dominic Porter Alexa Davies as Alexa Sophie Simnett as Blonde Student Seeta Indrani as Dr. Khan Cherrelle Skeete as Clare Lola Mae Loughran as Chrissie James Boyland as DS Cal Brown Leah Haile as Cocky Student Alex Okoampa as Rashan Shaheen Khan as Mrs. Palmer Heather Phoenix as Psychologist Kirsty Sawyer as Chloe Debra Baker as Mrs. Mills Yemisi Oyinloye as Desk Sergeant Helen Barford as Police Officer Paul Ryan as Mr. Mills