1 of 16
Business in the front, party in the back! In 1985, a 24-year-old George Clooney injects a little classic '80s sex appeal into the all-girl cast of The Facts of Life as George Burnett – the carpenter who is as handy with a hammer as he is with a can of mousse.
2 of 16
BOOKER THE LOOKER
As the charming, handsome boss Booker on Roseanne's first season, Clooney romances sister Jackie (Laurie Metcalf). But behind the scenes, it was the show's star who had designs on the actor! Clooney tells PEOPLE Roseanne Barr approached him with the pickup line: "'You're really good looking, why don't you take me out behind the stage and make me stink.'"
3 of 16
WHIP MY HAIR
Sporting shoulder-length curls – and that famous grin! – Clooney, here in 1990, lands a few minor roles (the sitcom Sisters and the fantasy Unbecoming Age), but doesn't hit his big break until four years later.
4 of 16
Women race to their television sets – and men race to the barber to copy his "Caesar" hairdo – when Clooney debuts as swoon-worthy Dr. Doug Ross on ER in 1994. "If you stuck a mannequin in my part, he'd get all the fan mail," the self-deprecating actor tells PEOPLE of his role, which he leaves in 1999.
5 of 16
FIT TO BE TIED
Now praised for his dapper black-tie appearances, a bespectacled Clooney skips traditional neckwear for a whimsical tie at the 1996 opening of the Broadway musical Rent.
6 of 16
The movie was admittedly bad, but Clooney (with Elle Macpherson) still looks so very good as debonair Bruce Wayne! "I had some tremendous Oscar buzz for Batman & Robin and I was, as you can imagine, disappointed," Clooney later jokes about his ill-reviewed 1997 turn as the Caped Crusader.
7 of 16
SEXY TIMES TWO
The actor lands on the cover of PEOPLE's Sexiest Man Alive issue in 1997, with the magazine praising, "Call it the Clooney maneuver. It's that little head tilt he does when his chin dips down and his eyes drop to the floor. Then, wham! Those eyes are back, full of mischief and magic, atop a sly half grin that all but announces, 'Yep, I'm trouble, but you love me anyway.'" He gets more love from PEOPLE in 2006, when he is again named the Sexiest Man Alive, only the third celebrity to receive the honor twice.
8 of 16
Those eyes! That suit! That smirk! The actor made Jennifer Lopez – and every other woman in America – faint with his turn as a career bank robber who seduces Lopez's U.S. marshal in 1998's Out of Sight. "It wasn't so bad for me," Lopez joked to Rosie O'Donnell about her steamy sex scene with the actor.
9 of 16
IN THE HEIST
Double your sexy, double your fun! Playing another charming criminal, Clooney teamed up with fellow two-time Sexiest Man Alive Brad Pitt for 2001's Ocean's Eleven. "I'm a method actor, so I spent years training for the drinking and carousing that I had to do in this film," jokes Clooney about his ladies' man rep.
10 of 16
One golden boy meets another at the 2005 Academy Awards, when a dashing Clooney (in his now-signature black-tie) accepts the Best Supporting Actor award for Syriana. "Sexiest Man Alive, 1997," he reminds the audience during his speech, before again making fun of his turn as Batman – twice.
11 of 16
LUCKY NUMBER THIRTEEN
In a crisp, open-necked white shirt and a tailored black suit, Clooney defines sexy at the 2007 premiere of Ocean's Thirteen, which costarred that year's Sexiest Man Alive, Matt Damon. "In the event that he can't serve, the former Sexiest Man can take over, so if he slips up, I'm ready to take back the crown," Clooney jokes to PEOPLE.
12 of 16
"It's difficult not to have chemistry with that man," his Up in the Air costar Vera Farmiga says, aptly summing up the charmer's appeal to The Seattle Times.
13 of 16
MAN IN BLACK
Another day, another sleek red carpet appearance. At Up in the Air's 2009 premiere, Clooney cuts a dashing figure in a black-on-black suit.
14 of 16
The actor arrives alone to the 2010 Academy Awards – and maintains that he's comfortable with his solo status, having famously bet Nicole Kidman and Michelle Pfeiffer $10,000 apiece that he would still be unmarried and childless when he turned 40 in 2001. "If anyone wants to make the same bet for when I'm 50," he said, "get in touch." (He hit that milestone last year.)
15 of 16
"I have the best date in the whole world," girlfriend Stacy Keibler said of her boyfriend, whom she accompanied to the November 2011 premiere of The Descendants, the film that earned Clooney his most recent Oscar nod.
16 of 16
SALT & PERFECTION
The salt-and-pepper-haired Clooney, here in February, has come a long way from his swanky '80s mullet – and he's perfectly okay with it. "You don't want to try to look younger because you'll look wrong. You dye your hair, you look wrong," he told Playboy. And Clooney, who turns 51 on May 6, is clearly doing everything right.