Guest Stars Mandeep Dhillon voices Telephone Caller Ellie White voices Telephone Caller London Hughes voices Telephone Caller Ed Gaughan voices Telephone Caller Jacob Scipio voices Telephone Caller Clive Mantle as Dennis Will Smith as Zak Shola Adewusi voices Telephone Caller Catriona Knox as Sophie Yasmine Akram as Hazel Leonie Elliott as Teaching Assistant Melanie Tom Basden as Aidan Scarlett Brookes as Amy Dario Coates as Nick Anya McKenna-Bruce as Ellie Yohanna Ephrem as Zadie