With its sentimental story and Sidney Poitier's portrayal of the principled Thackeray, the film was one of the highest-grossing movies of 1967. The title song, performed by Lulu, was an international hit. Assigned to a teaching post in London's East End, American Mark Thackeray had little idea the students had all been rejected from other schools, deemed to be unteachable. Subjected to ridicule and bullying, Thackeray gradually earns their respect and admiration realising the students needed a different kind of education than that of a textbook.