It’s not quite an ultra-villain origin story. But nor is Iranian-Danish director Ali Abbasi’s The Apprentice in any way a flattering depiction of its subject, the young(ish) Donald Trump (a horribly convincing Sebastian Stan). The film follows Trump’s early journey, starting as “Little Donnie”, the browbeaten second son of an overbearing father who scoffs that his boy “needs all the help he can get”. But, as the film tells it, the young Donald finds a second father figure in the well-connected and widely feared rightwing lawyer Roy Cohn (Succession star Jeremy Strong, bringing his trademark unblinking gimlet intensity to the performance, with chilling effect). The lessons learned from his mentor – chicanery, bluster, vanity and the need to win at all costs – shaped the Trump we know today.

It would have been easy to make Trump into a monster or a ridiculous figure of fun, and since Abbasi, who previously made the Iranian serial killer movie Holy Spider, isn’t known for his subtlety, it’s surprising and even a little disappointing that The Apprentice doesn’t go all in on the grotesque and extreme aspects of the Trumpian evolution. But it does show 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 impressionable man who mistakes bullying for strength and views power as something to be weaponised. Not surprisingly, Trump is irked by the depiction. His lawyers sent an unsuccessful cease-and-desist letter to the producers shortly after its premiere in Cannes in May, and last week on social media Trump described the film as a “politically disgusting hatchet job”. While a touch more savagery might have been satisfying for some sections of the audience, the fact the Donald has worked himself into a frothing, impotent rage about the film suggests that it must be doing something right.

The action opens in the battle-scarred New York of the 1970s. The young Donald is a hungry and ambitious small player on a big stage. He has plans to take over a derelict hotel in the blighted no man’s land of Manhattan’s Midtown. But so far, his father, Fred Trump (Martin Donovan), is dismissive of his son’s vision, preferring to employ Donald’s talents as a glorified rent collector for his down-at-heel Trump Village housing complex in Coney Island. Abbasi captures the character of the city with plenty of grainy shots of burning rubbish and yawning smashed windows. There’s jittery, amphetamine nerviness to the camerawork – as if whoever is behind the lens is half expecting to be mugged or stabbed.

Insulated by his father’s name, Donald is unfazed by the edginess of his city, his eyes firmly fixed on a gilded future of which he intends to be a significant part. To this end he rubbernecks at the rich and famous at a Manhattan members’ club (“They say I’m the youngest person ever admitted,” he brags to a bored blond woman), hoping to soak up their influence by osmosis. He catches the cold, shark-eyed gaze of Cohn, who invites him into an inner circle populated by the great and the not remotely good: smirking mafioso big shots, political power brokers and Rupert Murdoch.

Having untangled the Trump Organization’s knotty legal woes in his inimitable way, Cohn sets about moulding young Donald into a winner. He rattles off his three rules for success. No 1: attack, attack, attack. No 2: admit nothing, deny everything. No 3: always claim victory, never admit defeat. Donnie gazes at him like a newly hatched chick imprinting on its mother; he swallows Cohn’s wisdom whole and turns it into a personality. And with an All About Eve-style inevitability, the protege usurps the mentor and a force is unleashed.

Of the key central characters, Trump is arguably the least interesting – or at least the one who is still not fully formed. 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 city-sized ambitions. You get the sense that any boogying will be done on her own terms. And that she never called any man “sir”.

Most intriguing is Strong’s slippery portrayal of Cohn – a man full of sharp edges and wide, swinging contradictions. He was a closeted homosexual who, when he worked alongside Senator Joseph McCarthy, tirelessly persecuted the gay population. He’s depicted as someone who gets misty-eyed with pent-up emotion when he talks about his love for the US, but who despises huge swaths of the American population. And, the film argues, Cohn’s pernicious, far-reaching influence on the country he professed to serve is all too evident today, nearly 40 years after his death.