If You Don't Know Grey's New Hot Doctor, You Need to Watch More Early '00s Television

Carmack's starred in The O.C. from 2003 to 2004. He played Luke Ward, Marissa Cooper's jealous and brutish boyfriend. Luke's arc throughout the show is full of twists and turns, like his engagements in scandalous affairs and his discovery of his father's sexuality. Some fans may have felt a tinge of resentment towards him for beating up Ryan in the first season, but Luke turns out to be a mostly decent guy towards the end. Mostly.

Carmack appeared in one episode of the young Superman series back in 2005.

2005's Lovewrecked is one of the many goofy TV movies that launched Carmack's career on the small screen. In it he portrays Jason Masters, a famous rock star who's trapped on an island by a girl named Jenny (Amanda Bynes), a superfan who's in love with him. While he doesn't play another bad boyfriend in this romantic comedy, his character is a false romantic lead like Luke. It could be argued that Lovewrecked created the musical foundation for Carmack's role as a country idol in Nashville, though he looks a lot wackier here in his over-the-top rock gear.

Who could forget this 2006 Lindsay Lohan gem? Carmack appeared (with some suspiciously long hair) as David Pennington.

In the 2007 comedy Suburban Girl, Buffy the Vampire Slayer alumnus Sarah Michelle Gellar plays a timid book editor who pursues a relationship with a publishing philanderer portrayed by 30 Rock's Alec Baldwin. Amidst some of television's well-beloved darlings, guess who portrays Gellar's immature, morally questionable ex-boyfriend? Yup, Carmack is back at it again.

Following the footsteps of Ashton Kutcher and Eric Lively, The O.C. actor earned the leading role in the third installation of the sci-fi psychological horror franchise The Butterfly Effect. His character, Sam Reide, is a man who uses his time-traveling ability to uncover the details of a murder. Of course, Sam slips up during his investigation, and because of the butterfly effect, an evil serial killer emerges. If it sounds like a cult movie, it's because it is a cult movie, complete with a rugged, earnest protagonist and gratuitous gore for your viewing pleasure.

While it isn't necessarily a critical standout, 2009's Into the Blue 2: The Reef is good if you're into straight-to-video action flicks. He stars as Sebastian, a smokin' hot scuba diver who's very much in love with his girlfriend Dani. While the lovebirds are happy, they're also struggling with money, which leads them to take on a dangerous job from Sebastian's employer to look for sunken treasure.

Something like the antithesis of How to Lose a Guy in 10 Days, the 2010 TV movie Beauty & the Briefcase features the lovable Hilary Duff as a scrappy young journalist named Lane who takes on an assignment to find a good man in Manhattan's business district. As Lane goes undercover, hilarity ensues. Carmack plays Liam, a gorgeous, worldly Brit that Lane meets at a bar, but isn't really supposed to be seeing. By the end of the movie, we find out that Liam has a few secrets that he's keeping from Lane, because of course.

Carmack lent his voice to the 2010 animated movie Alpha and Omega, in which he portrays a sport brown wolf named Garth who doesn't know how to howl properly. While Garth is supposed to marry a light brown wolf named Kate (Hayden Panettiere), she doesn't love him. The actor returned to his role as the wolf in a direct-to-DVD release of a Christmas special titled Alpha and Omega 2: A Howl-iday Adventure.

The sexy actor is in another dramatic project set at the beach — but this isn't a teen soap. Nope, it's a full-blown shark horror movie developed by the producers of Hostel and The Texas Chainsaw Massacre. Carmack portrays Dennis Crim, the flirtatious ex-boyfriend of one of the movie's main antagonists, Sara. Years before they bump into each other, Sara accidentally scars Dennis's face. Very eerie indeed.

Of all of his roles, Nashville's Will Lexington is probably one of Carmack's sweetest. It's also the role that Carmack held onto the longest — the part spanned over a period of six consecutive seasons, ending in 2018. In the country musical drama, Will is a closeted gay singer-songwriter who eventually comes out to the country community and his family. Carmack's character is charming and caring to his partners and friends, a complete 180-degree flip from the actor's smarmy bad boy roles.