All Cast
Asa Butterfield
Nathan Ellis
Rafe Spall
Martin Humphreys
Sally Hawkins
Julie Ellis
Eddie Marsan
Richard
Jo Yang
Zhang Mei
Alex Lawther
Isaac Cooper
Alexa Davies
Rebecca Dunn
Martin McCann
Michael Ellis
Orion Lee
Deng Laoshi
Jake Davies
Luke Shelton
Paul J. Dove
John
Percelle Ascott
Ben Morgan
Christina Low
IMO Contestant
Edward Baker-Close
Nathan Ellis (9 yrs)
Suraj Rattu
Pav Kamdar
Jamie Ballard
Headmaster
Clare Burt
Doctor
Adam Foster
Paediatrician
Lee Zhuo Zhao
Li Jing
Shannon Beer
Caz
Tasha Connor
Jessie
Bo-Han Huang
Luke's Buddy
Song-Hung Chang
Employee
Lawrence Jeffries
Schoolboy