You’re not kidding!

When comic actors turn serious, there’s a monetary vacuum in the room; we’re not sure how to react, because we’ve been preconditioned to expect a punchline.

Anyone watching the Oscar-nominated drama Foxcatcher could be forgiven for suppressing a laugh when Steve Carell first shows up onscreen, prosthetic makeup extending his shnozz. Carell plays American billionaire John du Pont — but you might, for a second or two, be expecting him to launch into a classic Michael Scott routine from The Office.

When comic actors get serious, there’s a monetary vacuum in the room; we’re not sure how to react, because we’ve been preconditioned to expect a punchline. Instead, in Bennett Miller’s dead-serious Foxcatcher, a true story of a rich man’s obsession with Olympic wrestling, we get punched in the face by reality.

Put aside the prosthetic nose, and Carell delivers a perfectly understated, detailed depiction of a man locked into his own obsessions and self-deceptions. Not even Peter Sellers, playing Chauncey Gardiner in Being There, refrained from corpsing it completely — Hal Ashby tacked on an outtake of Sellers cracking up during the closing credits, take after take, as though to let the air of tension out of the room, to remind us all that Sellers was best known for playing Inspector Clouseau.

When comic actors try to get serious, bad things sometimes happen. They try to prove their range extends beyond pulling laughs from an audience, and they overextend. Bill Murray, who’d won plenty of fans with his slacker character in Stripes and Ghostbusters, went for a “serious” role in M. Somerset Maugham’s The Razor’s Edge — and bored everyone to tears. (He made a similar mistake playing Franklin Roosevelt in a recent biopic, though one suspects Murray doesn’t care what the world thinks of his acting either way.) Since then, Murray’s honed his sad clown’s persona to perfection in movies like Rushmore and Lost in Translation, walking the delicate line between comical and affecting.

Another pair of comedians from Saturday Night Live fame turned in serious roles for this year’s Sundance awardee, The Skeleton Twins. As brother-and-sister twins Milo and Maggie, Bill Hader and Kristen Wiig are a couple of siblings haunted by the suicide of their father and both contemplating a similar end as the movie opens. Not exactly the stuff of SNL skits.

Hader plays it straight, though his character is gay, and Wiig taps into reserves of dissolution and disappointment every time the camera comes in for a lingering closeup. This is the woman who ripped the box office to shreds with her comedy Bridesmaids, doing kamikaze karaoke at someone else’s wedding party.

Though the laughs come from the Craig Johnson screenplay, Wiig and Hader play it like serious Hollywood pros — take that, SNL alumni! — and only slip into more familiar comic territory during an over-the-top lip sync duet to Starship’s Nothing’s Gonna Stop Us Now (which, frankly, the movie benefits from).

Like singers who occasionally itch to prove they can really act — Jennifer Lopez in Out of Sight, say, or Jennifer Hudson in Dreamgirls — funny people might feel the overwhelming need to prove they’re more than just their comic persona.

Case in point: Jim Carrey. The man behind The Mask and Ace Ventura must have felt, somewhere around the time he was pulling in $20 million per silly role and being called the “funniest man in America,” that he needed to extend: his first bid for Oscar attention was The Truman Show which, despite early Academy buzz, was largely snubbed by the Oscars (though Carrey’s co-star Ed Harris was nominated for a Supporting Actor trophy).

This didn’t deter Carrey from trying to get serious again. And again. And again. Until people forgot he was supposed to be funny. Still, in Milos Forman’s Man on the Moon (about postmodern comic Andy Kaufman) and Michel Gondry’s Eternal Sunshine of the Spotless Mind, Carrey proved he had the chops. Oscar just wasn’t buying, and continued to snub his “serious” work (though he did bag an armload of Golden Globes).

It’s an odd snobbery that persists around comic actors, perhaps similar to the snubbing that Steven Spielberg and Alfred Hitchcock received from the Academy for so long. The imaginary line between “popular” and “art” didn’t keep millions from enjoying their work.

Yet some slip through the cracks, like Jonah Hill, who went from being Seth Rogen’s sidekick in Knocked Up and the penis-doodling high schooler in Superbad to an Oscar nom for (again) Bennett Miller’s Moneyball, then another one for playing demented broker Donny in Martin Scorsese’s The Wolf of Wall Street. (This despite wearing ridiculous false teeth and comic eyewear.)

And some, like Steve Martin, chip away at respectability from the outside, writing plays and collecting art and appearing in quiet little David Mamet dramas like The Spanish Prisoner. This has not stopped him, however, from doing Cheaper by the Dozen installments and putting on rubber noses in Pink Panther remakes.

Another funny man given to prosthetics is Mike Myers who, despite a serious comic bid in 54 (actually quite good as ‘70s disco owner Steve Rubell), could never really escape the Hollywood albatross of Austin Powers sequels and Shrek roles and bad Dr. Seuss movies. In short, he couldn’t escape comedy. Indeed, there are worse fates.

Perhaps the real bias against comedians who try to turn serious is that they’ve been having fun too long. They’ve been romping around in the playground of comedy, getting well paid, and somehow they deserve punishment for not impersonating an incorrigible ALS patient or early-onset Alzheimer’s sufferer. Instead, they took the low road, went for the low laughs. Much like Vanessa Redgrave’s distaste for her son John du Pont’s love of wrestling in Foxcatcher:  “It doesn’t matter. I’m glad you have your trophy. It can go in the trophy room, but not in the Rosemont case. I don’t like the sport of wrestling, as you know. It’s a low sport and I don’t like to see you being low.”