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 Leonie Elliott as Teaching Assistant Melanie Yasmine Akram as Hazel Tom Basden as Aidan Dario Coates as Nick Scarlett Brookes as Amy Anya McKenna-Bruce as Ellie Yohanna Ephrem as Zadie