Famously the first film based on a script by Ingmar Bergman, Torment (know as Frenzy for its initial British release) was financed by Svensk Filmindustri, the prestigious Swedish production company. With the arrival of sound, the era of masterpieces by such directors as Victor Sjöström and Mauritz Stiller (the discoverer of Greta Garbo) had come to an end: in the 1930s, Swedish audiences preferred a diet of light romantic comedies. But with the outbreak of war, which restricted the circulation of foreign films and raised the moral issues of Swedish neutrality, there was a fresh demand for serious themes. In 1942, the newly-appointed head of Svensk, Dr. Carl Anders Dymling, recruited Sjöström as artistic director of the company's production programme, and even maintained a script department with the specific daily purpose of sifting out appropriate material.

Ingmar Bergman was awarded a year's script-hunting contract at the start of 1943, on the strength of one of his own plays having been successfully staged by the Student Theatre in Stockholm. He wasted no time in offering an expanded short story he had written about his final year as a student. The project went unnoticed until, having hired Alf Sjöberg for an anniversary production, the studio realized it had nothing for him to direct. In his introduction to Four Bergman Screenplays, Dymling recalls that "a manuscript suddenly appeared on my desk, not a scenario but a short novel intended as a film. It was a startling experience: here was a very angry young man—long before they became the fashion—a writer looking at the world through the eyes of a teenage rebel, harshly criticizing his parents, offending his teachers, making love to a prostitute, fighting everything and everybody in order to preserve his integrity and his right to be unhappy. This was how Bergman started his career in motion pictures."

Alf Sjöberg was primarily a man of the stage, hugely admired by the young Bergman from his earliest theatre-going days, and only recently back in favour with his second film, They Staked Their Lives (1939). He adapted Torment under two main influences: firstly, both he and Bergman had endured—at different times—the same sadistic teacher (known as 'The Coachman' for his verbal lashing of students), and secondly, the story echoed the anti-Nazi sentiments of Sjöberg's productions at the Royal Dramatic Theatre in Stockholm, his lifelong base. Too delighted at the opportunity to observe the filming process to offer much argument, Bergman accepted the role of 'script girl' and was ejected from the set from time to time for making mistakes and being helpful.

Later, he was to remark that Sjöberg's versions—in which Caligula is made to resemble Himmler and reads the Swedish pro-Nazi newspaper Dagsposten was a little too much of a period piece, with allusions that are no longer relevant or even recognizable. Certainly the film 'reads' like a first chapter in a text that Bergman has updated throughout his career.

To deconstruct Caligula from inexplicable tyrant to emotionally wounded loner is to discover a clear affinity with other Bergman couples—the Knight and the Squire in The Seventh Seal, for example, or the weary duellists of The Silence and Persona. His fear of himself is basic Bergman, while the unending struggle against authoritarian parents and their allies has also been an agonized constant. Interestingly, Torment even illustrates the smug omnipotence of the medical profession, anticipating the dismissive abortionist in Port of Call and the glacial nurses of Waiting Women and So Close to Life.

What both Sjöberg and Bergman had learned from their stagecraft translates to the screen with a wholly enjoyable vitality. Sjöberg was an admirer of Pudovkin and Eisenstein, but here and in his subsequent studies of sacrificial fatalism, Miss Julie (1951) and Kären Mansdotter (1954), he appears more loyal to the sweeping staircases and choking shadows of the German Expressionists. He makes something of a horror-movie meal out of the attacks on the inoffensive Bertha, and the clutching hand-shadow on the stairs is unforgivable, but the grand arches of the school building (where both Sjöberg and Bergman's brother, Dag, were educated) form a splendid entrapment, as if Escher were somehow fused with The Exorcist.

Impervious to the Bergman gloom, his producers made a habit of insisting on up-beat endings, last minute reversals that make little sense (see Crisis and Port of Call). In Torment, the late amendment is the Headmaster's visit to Jan-Erik's room: without it the film would have ended, cynically enough, with the downpour promised to the students as part of their brave new world, and with Caligula waving cheerily from a window. Rewritten to include the Headmaster's platitude—"I've found there's usually some good in everything that happens"—the final shots are now of Jan-Erik clutching a kitten in the morning light.

In his autobiography Images: My Life in Film, Bergman reveals that these shots formed his film-making debut: "I was more excited than I can describe. The small film crew threatened to walk off the set and go home. I screamed and swore so loudly that people woke up and looked out their windows. It was four o'clock in the morning." Since the impression conveyed by the screen was of Jan-Erik sinking into the ground, Bergman would probably have shot it differently within a year or so. But it was a start.