Guest Stars Layton Williams as Stephen Carmichael Charlie Wernham as Mitchell Harper Kae Alexander as Jing Chow Ethan Lawrence as Joe Poulter Nikki Runeckles as Chantelle Parsons Jack Binstead as Rem Dogg Jack Bence as Frank Grayson Harry Enfield as Martin Wickes Hilary Whitehall as Mrs Carmichael Samantha Spiro as Professor Celia Green Phoebe Waller-Bridge as India Delroy Brown as Mr Richard Carmichael