Despite its title, it has nothing to do with cigarettes. But its star, as he once famously said on screen, is absolutely “smokin’.”

Jim Carrey is the narrator,  heart and soul  of “I Love You Phillip Morris,” transforming what could have been a cliched con man comedy, generic Jim Carrey character comedy or run-of-the-mill  gay coming-out comedy into something smarter, sweeter and downright giddy. This long-shelved romp is a real Carrey showcase, one that shouldn’t wear the stigma “damaged goods” simply because it took an absurdly long time — it was at Sundance in January of 2009 — to reach theaters.

Carrey plays Steven Russell, a one-time cop, married man and father who lives a secret double life until that day when a bad car wreck sends him over the edge.

“I’m gay,” he babbles on the EMT’s gurney. “Gay gay gay gay gay gay gay.”

Bad news for his fundamentalist wife (Leslie Mann, perfect at playing “long-suffering”). Now she has something bigger than “Thank you for helping me find that coffee filter today” to say to Jesus each night on her knees.

In a flashback hilarious for its cruelty, we’ve watched the 10 year-old Steven learn that he’s adopted, and we’ve been told he only joined the police force “to find my birth mother.” His needy, over-the-top confrontation with that birth mom is just another instance where he fails to find himself or feel loved. Steven has a hole in his soul.

But out of the closet, Steven gleefully cruises Miami. The con man in him comes to the fore when he makes one unpleasant discovery about his new, free-wheeling life style.

“Bein’ gay is expensive,” he drawls.

Steven weasels his way into work in Texas, where his gift for living a lie — many lies — makes him a grand con man. but it’s when he gets caught and sent to prison that he truly thrives, and not just because of the opportunity for a glad-handing con-man like him to ingratiate himself into “the system” or the many same-sex romantic options. It’s in stir that Steven meets his dream boat, Phillip Morris, played with a drawling delicacy by Ewan McGregor.

The bulk of this -”really happened, it really did” story concerns Steven’s efforts to be close to Philip, to (once they’re out of jail) provide an opulent life for Phillip and stay one step ahead of those who might find him out in his various hustled jobs — lawyer, accountant.  Co-writers and co-directors John Requa and Glen Ficarra conjure up an offbeat “How to Succeed in Business Without Really Trying” meets “Dog Day Afternoon” gay romance that has us rooting for Steven and Phillip from the moment they meet, and Steven coos “This right here? This is destiny.”

And when things turn dark, as they often do when your whole life is a lie, we fear for them, especially Steven, whose genius for hustling folks is matched with greed, all channeled into his mania for Phillip.

It’s a tribute to McGregor that his trademark sparkle makes us believe, every minute of this film, that a nut like Carrey’s Steven would fall for him and go to the ends of the Earth — or prison in Texas — to earn and keep his love.  And it is Carrey, turning his patented rubber-faced, rubber-voiced shtick loose on a role with heart, substance and entertainment value, who makes this romantic farce a movie too good to sit on any studio’s shelf. 

Cast: Jim Carrey, Ewan McGregor, Leslie Mann

Directors: Glenn Ficarra, John Requa

Running time:  1 hour 42 minutes

Rating: R for sexual content including strong dialogue, and language.