Kevin Federline by Denise Truscello/WireImage.com Kevin Federline by Denise Truscello/WireImage.com

While his former missus' own comeback tries to get out of its own way, Kevin Federline is busy enjoying his visit to One Tree Hill. "I'm really into the acting thing," he tells TV's Extra. "I'm loving it!"

For the multi-episode stop-by, K-Fed is playing a Tree Hill native named Jason, whom he sums up as a "self-obsessed wannabe rock star. You know, a guy that really takes himself too seriously."

Yeah, we used to know "that guy." Wore trucker hats. Jeans around his thighs. Nice to see he's mellowing out.