The initial conversation around Tom McCarthy's 2003 directorial debut The Station Agent was centered on why the filmmaker opted to cast a little person in the lead role when the part wasn't specifically tailored for such an actor. But in Peter Dinklage, McCarthy discovered a star, and Dinklage's performance was so striking that other filmmakers began writing little people into their scripts just to work with him. It wasn't long before Dinklage was being cast in roles that made no reference to his stature. Today, nobody bats an eyelid when Dinklage is cast in the sort of roles a little person would never have been considered for a couple of decades ago.

Could writer/director Aaron Schimberg's A Different Man do for actors with neurofibromatosis as The Station Agent did for little people? Could actor Adam Pearson - previously briefly seen as one of Scarlett Johansson's victims in Under the Skin and in a lead role in Schimberg's lesser seen previous feature Chained for Life - have an unlikely career in the manner of Dinklage? Conventional thinking would say his condition and its resultant severe facial disfigurement precludes him from being cast in any "regular" roles that don't explicitly reference his looks. But didn't we think the same about Peter Dinklage not so long ago? Pearson is such a charismatic force of nature in A Different Man that when the credits role you'll find yourself excited to see his next role, whatever form it takes. He possesses such an infectious energy that we fully buy into the idea of the character he plays, Oswald, being able to win over everyone he encounters in spite of his appearance.

Conversely, we also accept Sebastian Stan as a man who feels deeply uncomfortable in his skin, despite looking like...well, Sebastian Stan. When we initially meet the Hollywood heartthrob his chiselled features are buried under prosthetics. He plays Edward, who like Pearson, is afflicted by neurofibromatosis. Edward is an aspiring actor, but thanks to that aforementioned conventional thinking, he's only been able to land a part in a laughably patronising corporate training video on how to deal with disfigured co-workers. Eternally conscious of his appearance, Edward walks with a slouch and keeps his head down, avoiding human contact where possible. Even friendliness makes him uncomfortably self-aware, like that of his new neighbour, beautiful Scandinavian wannabe playwright Ingrid (Renate Reinsve).

In similar fashion to this year's similarly themed The Substance, a visit to the doctor leads Edward to a radical new experimental treatment that may cure his condition. Edward volunteers for the experiment but isn't told whether he's actually receiving the treatment or is part of a control group being fed placebos. As Edward finds his skin gradually peeling away, it becomes clear that he is indeed receiving the treatment, and it's working wonders. When his old face eventually falls away he's left looking like Sebastian Stan. Creating a story that Edward committed suicide, he assumes a new name, Guy.

Some time later Guy is a successful real estate agent, his handsome face plastered all over New York adverts. But inside he's still Edward. He still walks with a slouch and drooped shoulders, and he's uncomfortable when his looks are acknowledged, as though he feels like a fraud, or he's betrayed his old self. One day he stumbles across Ingrid and discovers that she's holding auditions for a play called "Edward," which is based on her friendship with the man she believes killed himself. Guy decides to audition but initially flops. Trying out a second time with a mask his doctors made of his old face, Guy not only wins the part but begins dating Ingrid.

Enter Oswald, who arrives to try out for the part only to concede that Guy is a better choice, despite Oswald sharing the very same condition as "the late" Edward. Guy is unsettled by Oswald, who begins appearing everywhere he goes. Unlike Edward, Oswald refuses to let his appearance define him, and he easily wins friends with his charming nature. Guy begins to worry that Ingrid is considering replacing him with Oswald, both in her play and her life.

Schimberg seems heavily influenced by Woody Allen, with a supporting character even likening Edward's awkward manner to the nervous persona of a young Allen. The plotline is reflective of the dream in Stardust Memories, where Allen finds himself on a train surrounded by miserable ghouls while the carriage on the opposite track is filled with partying beautiful people, including Sharon Stone. Edward/Guy feels like he's been cheated, stuck in life's miserable carriage while the party rages across the tracks. It's a bitterness most of us can relate to, even if we'd rather not admit to it. Haven't we all seen successful people and wondered what they have that we don't? For Edward it's an especially cruel irony given how we was treated prior to his transformation. It wasn't simply a case of him allowing his self-consciousness to affect him; he was othered by society in a way that Oswald seems to have escaped. Rather than feeling good for Oswald, Edward/Guy feels nothing but resentment.

A Different Man also feels like an American cousin of the recent wave of Scandinavian social satires. The casting of Reinsve suggests he's a fan of Joachim Trier's The Worst Person in the World, while his film shares themes with Kristoffer Borgli's Sick of Myself, in which a conventionally attractive young woman finds she gets more positive attention when she becomes deformed as a result of taking a banned drug. There's a level of blackly ironic humour here that we haven't seen in American cinema since the heyday of Todd Solondz.

Along with tackling society's obsession with looks, A Different Man raises other interesting questions. The film industry currently finds itself walking on eggshells when it comes to representation, satirised here in Ingrid's dilemma over whether to cast the handsome Guy in make-up or the real deal Oswald. Ironically, Pearson and Stan are both equally excellent here, and the fact that many viewers have actually confused Stan's prosthetic performance as Edward with that of Pearson's suggests that this is a dilemma that will rage on for some time when it comes to screen representation. Edward/Guy's sense that he's not getting everything he believed would come his way with a conventional face echoes the resentment we currently see in a lot of young white men, bitter that they can no longer enjoy the advantages their whiteness and maleness afforded previous generations. For all of its anti-hero's dyspeptic bitterness, A Different Man ends on a hopeful note that suggests we all need to make peace with ourselves and stop envying others, and that true ugliness is something we wear on the inside.

Directed by: Adam Schimberg

Starring: Adam Pearson, Sebastian Stan, Renate Reinsve, C. Mason Wells, Owen Kline, Charlie Kosmo, Patrick Wang, Michael Shannon