IIt's not exactly an ultravillain origin story. But not that of the Iranian-Danish director Ali Abbasi either The apprentice in some way a flattering portrayal of its subject, the young Donald Trump (a terribly convincing Sebastian Stan). The film follows Trump's early journey, starting as “Little Donnie,” the intimidated second son of an overbearing father who jokes that his boy “needs all the help he can get.” But as the film tells it, young Donald finds a second father figure in the well-connected and widely feared right-wing lawyer Roy Cohn (Consequence Star Jeremy Strong brings his signature, unwavering Gimlet intensity to the performance, to chilling effect). The lessons he learned from his mentor – bullying, bluster, vanity and the need to win at all costs – shaped the Trump we know today.

It would have been easy to make Trump a monster or a ridiculous figure of fun, and that has been the case since Abbasi, who previously made the Iranian serial killer film Holy spiderHe's not known for his subtlety, which is surprising and even a little disappointing The apprentice does not exclusively address the grotesque and extreme aspects of Trump's development. But it shows a side of the former US president that you suspect he would prefer not to be seen. This Trump is an unexpectedly weak and malleable figure; an easily influenced man who mistakes bullying for strength and sees power as something that can be used as a weapon. Unsurprisingly, Trump is upset by the portrayal. His lawyers sent an unsuccessful cease-and-desist letter to producers shortly after its Cannes premiere in May, and last week Trump called the film a “politically repugnant hatchet” on social media. While a little more savagery might have been satisfying for some segments of the audience, the fact that Donald worked himself into a seething, impotent rage over the film suggests that he must be doing something right.

The action begins in war-torn New York in the 1970s. Young Donald is a hungry and ambitious little player on the big stage. He has plans to take over a run-down hotel in the seedy no-man's land of Manhattan's Midtown. But for now, his father, Fred Trump (Martin Donovan), remains hostile to his son's vision, preferring to use Donald's talents as a glorified rent collector for his dilapidated Trump Village apartment complex in Coney Island. Abbasi captures the character of the city with lots of grainy shots of burning trash and yawning broken windows. The camera work is nervous and amphetamine-like – as if the person behind the camera was half expecting to be attacked or stabbed.

Isolated by his father's name, Donald is unfazed by the nervousness of his city; his eyes are firmly set on a golden future in which he wants to be a key part. To that end, he attacks the rich and famous at a Manhattan members' club (“They say I'm the youngest person ever admitted,” he boasts to a bored blonde woman) and hopes to absorb their influence through osmosis. He captures the cold, shark-eyed gaze of Cohn, inviting him into an inner circle populated by the great and not remotely good: grinning Mafioso big shots, political power brokers and Rupert Murdoch.

After Cohn untangles the Trump Organization's complicated legal problems in his inimitable style, he sets out to mold the young Donald into a winner. He lists his three rules for success. #1: Attack, attack, attack. No. 2: Admit nothing, deny everything. #3: Always claim victory, never admit defeat. Donnie stares at him like a newly hatched chick imprinting on its mother; he swallows Cohn's wisdom whole and transforms it into a personality. And with one All about Eve-Style inevitability, the protégé usurps the mentor and a power is unleashed.

Of the central characters, Trump is probably the least interesting – or at least the one who hasn't fully developed yet. In contrast, his first wife Ivana (Maria Bakalova, excellent) knows exactly who she is. Abbasi gives her the musical motif of Baccara's disco stomper “Yes Sir, I Can Boogie,” which is slightly misleading: Ivana is an aspiring businesswoman with big-city ambitions. There's a sense that all drinking is done on their own terms. And that she never called a man “sir.”

Most fascinating is Strong's slippery portrayal of Cohn – a man full of sharp edges and big, swinging contradictions. He was a closeted homosexual who, while working with Senator Joseph McCarthy, tirelessly persecuted the gay population. He is portrayed as someone whose eyes become misty with pent-up emotions when he talks about his love for the United States, but who despises large parts of the American population. And, the film argues, Cohn's damaging, far-reaching influence on the country he claimed to serve is all too evident today, nearly 40 years after his death.