You might not have been rooting for him when he played the rough-and-tumble villain Cato in The Hunger Games, but Hollywood is developing an appetite for Alexander Ludwig, 19, previously best known for his role as Seth in 2009's Race to Witch Mountain, in which he played opposite "The Rock" Dwayne Johnson.

The Canadian Ludwig was first discovered when he was cast in a Harry Potter toy commercial, which launched him into movie auditions. He got his first bit role in a DVD film called Air Bud World Pup, about a boy and his soccer-playing dog, in 2000. Ludwig's starring role in 2007's The Seeker, however, with Ian McShane and Frances Conroy, is what put him on the map as a contender for heftier fantasy roles.

That was almost five years before Ludwig beefed up to play Cato, the character he would come to think of as exhibiting "the dark side of humanity." The young Ludwig took his role in the blockbuster very seriously. "That was the reason I did the movie, really," Ludwig told Celebuzz about channeling the amoral character. "If I could get the audience to sympathize with Cato for one second at the end of that movie, I did what I wanted to do."

So, does the new hot star have a girlfriend? Last week Ludwig was caught on video locking lips with Hunger Games costar Leven Rambin (of All My Children, Grey's Anatomy, One Tree Hill, and CSI: Miami), 21, who plays Cato's cautious ally in the film. However, a rep for Ludwig denied that he and Rambin are anything more than "party pals," according to E! Online. "They are not dating, they are friends," the source added.

"They hang out a lot and definitely go out together," an insider from the The Hunger Games said. "They're young and famous. They both like to go out and definitely enjoy having a good time."

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