At 10, Hamm, whose parents divorce when he's 2, loses his mother Deborah to cancer. He moves in with his father Daniel – a salesman who runs the family trucking business – and excels at St. Louis private school John Burroughs, where he plays middle linebacker and the lead in the school's production of Godspell.
A sophomore at the University of Texas, Hamm loses his father to diabetes and poor health. He returns home to St. Louis, where he completes his studies at the University of Missouri – before packing up for Los Angeles in 1995. "Losing both parents at a young age gave me a sense that you can't really control life – so you'd better live it while it's here," he tells Parade in 2010. "I stopped believing in a storybook existence a long time ago. All you can do is push in a direction and see what comes of it."
Struggling to make a name for himself in Hollywood, Hamm gets a call from writer-actress Jennifer Westfeldt, who's casting her play Lipschtick – the basis of her acclaimed indie Kissing Jessica Stein. Hamm and Westfeldt hit it off onscreen (he lands a role in her 2001 film) and offscreen, with the pair embarking on a decade-long relationship that eventually grows to include a dog, Cora.
While waiting tables, Hamm scores his first substantial acting gig – a recurring role on the TV drama Providence. Around this time, he appears in the Mel Gibson film, We Were Soldiers, and a slew of TV roles follow, enabling him to quit his day job. "I've probably been a waiter longer than I've really been anything else," he tells Vanity Fair of finally getting his Hollywood break.
Hamm gets the role of a lifetime, being cast as mysterious Madison Avenue ad executive Don Draper in AMC's first original series, Mad Men. The show earns him a Golden Globe win for outstanding lead actor in 2008, as well as repeated lead Emmy nominations. "We knew some people were watching and liked it," Hamm tells EW. "But to get the actual validation of 'We think you're the best' is amazing – and totally unexpected."
At the height of "Mad Mania," Hamm switches gears, hosting Saturday Night Live, where he mocks his TV character and even hawks Jon Hamm's John Ham ("The Ham You Can Eat in the Bathroom"). "He has that ridiculous sense of humor that we like to employ, a chasing-the-giggle kind of fun that’s dark and weird," longtime pal comedian Sarah Silverman tells Elle. In 2010, the actor returns for more gags, with two more hosting stints on SNL.
Hamm is named one of GQ's Men of the Year, sharing the honor with fellow cover stars President Barack Obama, Leonardo DiCaprio and Olympian Michael Phelps. "I've been incredibly lucky in many ways," says the actor, who stars in the sci-fi blockbuster The Day the Earth Stood Still. "I'm working on something that I really enjoy; I've been really fortunate. I've been waiting around a long time, but I'll take it."
Continuing to show that he's more than a man in a suit, Hamm begins a recurring stint as Tina Fey's love interest Dr. Drew Baird on 30 Rock. Of working with the hunky star, Fey jokes, "I haven't actually looked straight at him yet since he's been here. I poked a hole in a paper plate and I look at him like that, like an eclipse."
Building his film résumé, Hamm plays cops and robbers in actor-director Ben Affleck's Boston thriller, The Town. Of casting the Mad Men star, Affleck says Hamm "is really my idea of a man's man, which made it easy to portray him as a hero." The crime drama, which costars Blake Lively, Rebecca Hall and Jeremy Renner, debuts at the top of the box office, earning $23.8 million.
Hamm re-teams with his longtime love, writer-director Jennifer Westfeldt, on her latest film effort, Friends with Kids. "We were very proud," the actor said of working with his girlfriend, "and we put a lot of our own equity – and sweat equity – and emotional equity into all of that and that can sometimes not go so well, and it went really well."
BIOGRAPHY (top to bottom): Stephen Shugerman/Getty; Everett; Frank Ockenfels/AMC; Dana Edelson/NBC; Mark Seliger/GQ; Everett; Claire Folger/Warner Bros.; Charles Sykes/AP