Guest Stars Orla Bayne as Young Holly Mark Strepan as Rory Sawyer Sorcha Groundsell as Elizabeth Smith Emun Elliott as Alistair McDermid Chris Fulton as Charlie Lamont-Smith Evie Brassington as Young Georgia Daisy Littlefield as Lisa Grace Greatorex-Watson as Milly David Elliot as DS Tom Gillespie Siobhan Redmond as University Dean Clare Yuille as Invigilator