It is the last day of term at the Gilda Ball Academy, and teacher Martin Hicks starts it full of hope - he is about to get the promotion he's wanted for yearsand - good intentions, vowing to make things up with his estranged wife Helen. Cut to a dim, dark basement room in Elephant and Castle, where Bela, a Hungarian boy, lives with his great-uncle, a refugee from the Second World War, and his mother, a chain-smoking Communist. Bela has been threatening revenge on Martin ever since being suspended from Gilda Ball a few weeks previously following a playground riot during which a teacher died. He believes it was Martin who grassed him up...