The 2000s were filled with very interesting film, TV, and musical celebrities. It was also the dawn of reality television. With it came several stars who made it big on the big and small screens, but never seemed to duplicate their success today, given the cutthroat Hollywood industry. Here are just some of the 2000's most familiar faces that we don't get to see much of anymore, but were once the apples of our eyes. Check out these 5 #TBT celebrities you probably forgot existed.

Kristin Kreuk

Kristin Kreuk's bi-racial beauty caught the world's attention back in the early 2000's when she played the role of Lana Lang in the massively successful "Smallville" franchise, alongside the equally gorgeous blue-eyed heartthrob, Tom Welling.

It was her unique, mixed-race features that made her one of the most memorable faces, but it seemed that she could not bank on her looks alone to maintain a successful TV career. "Smallville" remains, to this day, her biggest role ever, but she did appear in "Beauty and the Beast" and is now the executive producer and star of "Burden of Truth," a Canadian television series on CBC.

Shane West

Those who were in their awkward tween/teen stages in the early 2000's will never forget their first big screen bad boy heartthrob, Shane West, who played Mandy Moore's on-screen first love, Landon Carter in the biggest movie of 2002, "A Walk to Remember," which was Adam Shankman's first major success on film before he ever thought of "High School Musical."

Frankie Muniz

Frankie Muniz was one of the most popular child stars at the time.

He starred as the titular character in "Malcolm in the Middle," a role for which he earned two Golden Globe Awards nominations and an Emmy nod. But, after he failed to replicate that show's success, he went behind the scenes, pursuing a career in writing and producing television shows. Now, he's still busy working backstage, managing musical artists.

But he did make a momentary TV comeback with "Dancing with the Stars."

Jesse McCartney

Singer/actor Jesse McCartney is another one of those blue-eyed heartthrobs who stole hearts in the early 2000's. His most memorable hits were "Beautiful Soul" and "Because You Live." As another one of those manufactured pop artists, this young man grew up in show business, so audiences watched him develop an edgier, sexier sound when he grew older. Unfortunately for him, it wasn't received well by his fans and he was forced to go into acting with roles in TV shows such as "Army Wives" and "The Walking Dead."