Guest Stars James Clack as Young Martin Jake Curran as Padraig Pearse O'leary Izabella Urbanowicz as Rosie Demarczyk Françis Renaud as Paul Capoue Héléna Soubeyrand as Clothilde Nathaniel Spender as Young Jean Maxime Lefrançois as Romain Damien Taranto as Nico Vincent Riotta as DCI Tom Kendrick Kirsty Dillon as Lorraine Andrew Whipp as Gareth Harriet Creelman as Gallery Manager