Actors Charlie Sheen (L) and Ashton Kutcher are seen in this combination file photograph created May 12, 2011. Kutcher was reported on Thursday to have signed a deal to replace Charlie Sheen in a revamped version of top-rated U.S. television comedy "Two and A Half Men." Deadline Hollywood said Kutcher, 33, the husband of actress Demi Moore, had signed a deal to join the cast of the CBS show when it returns for a ninth season. Sheen was fired in March from his starring role as a womanizing bachelor after weeks of erratic behavior and for publicly insulting the producers.[Photo/Agencies]

NEW YORK – Ashton Kutcher is not gnarly.

That simple fact makes the news that he'll be taking Charlie Sheen's place on "Two and a Half Men" highly intriguing. It also helps capture the degree to which Kutcher strikes a contrast image-wise to Sheen. And how, presumably, he will put a new spin on the hit CBS sitcom Sheen was fired from.

Bottom line: Whatever gnarly means, Kutcher isn't it — whereas, in Sheen's lexicon, it stands for much of what he famously celebrates and claims to be.

On Friday, CBS and Warner Bros. Television announced that Kutcher will join TV's top-rated comedy next season.

This switcheroo will be nothing if not profound.

For starters, Kutcher is a baby-faced 33 years old, while Sheen is a sharp-featured, party-hardened 45.

The character that Sheen played for eight seasons on "Men" — a fast-living, womanizing cad — drew comic inspiration from Sheen's own life of sex sprees, serial marriages and substance abuse.

On the other hand, Kutcher has a bit tidier public image: He has been rather quietly married for almost six years to Demi Moore (who, in contrast to Sheen's choice of partners, is older — by 15 years — rather than lots younger than her mate).

Kutcher first found sitcom stardom more than a decade ago as the lovable but goofy teen, Kelso, on "That '70s Show," and, on-screen since, he has retained a puppydog wholesomeness, an affable sexiness that translated to his romantic comedies. He is a sensitive, mischievously unassuming stud.

Consider the description by New Yorker film critic David Denby reviewing Kutcher's recent film, "No Strings Attached": "He seems puzzled a lot of the time, a little slow, though slyly amused around women. He's not offensive in any way. He's even rather likable."

Rather likable, indeed.

By contrast, the character Sheen played on "Men," Charlie Harper, wasn't meant to be likable so much as glorified for living the male dream.

"I make a lot of money for doing very little work," Charlie Harper boasted on the show's premiere in 2003. "I sleep with beautiful women who don't ask about my feelings. I drive a Jag. I live at the beach."

Charlie was speaking to his dweebish, high-strung chiropractor brother, Alan (Jon Cryer), whose wife had just thrown him out of the house. Alan and his son, Jake (Angus T. Jones), had crashed with Charlie. There they stayed.

The gist of "Men" lay in the disparity between Charlie's life of plenty and Alan's frustrated existence.

"My life is pathetic," Alan moaned on an episode this season. "On the other hand, Charlie's life is great."

But now Charlie is gone.

The big question that had weighed on the minds of "Men" handicappers since Sheen got the boot more than two months ago — who the heck will replace him? — was settled with Friday's announcement.

But other questions arise as Kutcher prepares to join Cryer and Jones in the sitcom's ensemble.

One of them: What role will Kutcher play, and how will that new character reassert the show's crucial dynamic between a man who thinks he has it all and another man who's pretty sure he has nothing?

Meanwhile, will this change be acceptable to the huge audience (more than 14 million viewers weekly) who liked "Men" just fine the way it was, with Sheen?

Now that Chuck Lorre, the creator and executive producer of "Men," has the new man, his challenge is how to make the new man fit.

Recall a wisecrack from this season when, with mock sympathy, Charlie Harper told his brother, "I get it. You're bored, you're lonely, you can't afford a hooker."

While waiting for "Men" to return for Season 9 this fall, many fans of the show could be wondering: What would Ashton Kutcher say, instead?