Troell, his collaborator Forslund, and Clas Engström, on whose 1957 novel the film is based, were all former teachers, but this is no recruiting poster. Shot in Troell's old school in Malmö with compact 16mm equipment and minimal crew, it's a story of disintegration, boasting a brilliantly nervy central performance from Bergman regular Oscarsson as a teacher who oversteps the mark in trying to retain control of his rowdy pupils. It's a sign of his insecurity, a product (yet also a cause) of his wobbling marriage, but the kids can see the fear in his eyes and confrontation escalates. Troell's whirling hand-held footage is rather of its time, but it is undeniably effective in crowding out the increasingly cowed protagonist, a representative of a flawed authority that has seen its day. In retrospect, typically '68, and a worthy winner of that year's Golden Bear at Berlin.