It’a interesting to speculate what draws an actor to a particular part. Especially when it’s so unlike anything else they’ve done. In this case, the question is what exactly is rubberfaced clown Jim Carrey doing playing a gay conman in I Love You Phillip Morris? He’s shown in Truman Show and Eternal Sunshine of the Spotless Mind that he’s got an eye for a challenging role in a well-written film that has some substance — a world away from the annoying shtick he’s normally associated with.

The film is based on an improbable true story about Steven Russell, a man leading an outwardly respectable life who decides to be honest about who he really is when he experiences a near-fatal car crash. From church organist and father of an adorable daughter, he moves to Florida where he finds a boyfriend and begins to lead a lifestyle based on immediate gratification that he can’t actually pay for. You always end up paying for the things you can’t pay for, and Steve does time in prison for his conniving duplicitous ways. While there, he meets blonde blue eyed Phillip Morris, and is soon smitten, wanting to spend his life with this new love interest.

What’s impressive is that the story does’t shy away from the gay aspects of prison life — it’s clear that anything can be had for a price, whether money or offering someone a blowjob. This is a mainstream film about gay men where those gay men have sex, which some films pussyfoot about. Steven and Phillip’s story isn’t just an adorable romance — it’s an adorable romance with the physical action that films about men and women together let us in on, and is all the better for that. Whether it is also responsible for the film’s weak performance — it was showing four times a day for a week and is now going to once a day in its second week — I couldn’t tell you. Maybe Carrey fans aren’t so much homophobic as unused to seeing their star outside his usual context.

Ultimately it’s a story about a man discovering different versions of himself in the course of his love for someone else. And in the end being punished for the self that he truly offers to Phillip without the gameplaying that the rest of their relationship has been characterised by. He’s lied and cheated to have Phillip in his life, but there comes a point when Phillip will tolerate that no more — and Steven continues to love him, from a prison cell where he’s locked up 23 hours a day. In the end, Steven’s audacity challenged the powers that be in Texas — another way of saying the Bush family — and he is punished for that beyond any reasonable degree.

It’s a fascinating tale, all the more so for being a true one. John Requa and Glenn Ficarra write and direct the story perfectly, following Steven as he sheds first one skin, then another, and another still. At its most harrowing, the film follows Steven while he is dying of AIDS, only to reveal that this is one more breathtaking piece of chicanery by a master trickster who even gets away with faking his own death. And that’s what takes this film into deeper darker territory than Spielberg ventured into with Catch Me If You Can, his breezier take on the life of a con artist.

That willingness to go to the brink of death is ultimately what distinguishes Steven from other screen con artists. And it’s what appealed to Carrey, I’m sure. Known for twisting his face and body any which way in pursuit of a laugh and more applause, here Carrey gets to the roots of someone whose talent for deceit exceeds his own. In the process, Steven finds love, and finds himself. Put like that, you can understand why chameleon Carrey would be tempted to portray Steven onscreen.