NCIS: Los Angeles has established itself as a bona fide success in its freshman season, buoyed by heart-stopping, pulse-pounding episodes like this week's "Found."

Still, there's plenty of character development to be desired. As luck would have it, a G. Callen-centric season finale May 25 should uncover a couple of mysteries.

"We have this huge trail, leading us to some potential answers about Callen's past and who he is," Barrett Foa (Eric) tells TV Guide of Chris O'Donnell's character.

"We do get closer to it, and I think the fans will be satiated in some way."

The episode title? "Callen, G." In the NCIS: L.A. pilot, he revealed to Hetty that even he doesn't know what G stands for, as no one ever told the orphan as a boy.

What will we learn about this mysterious character's past this month?

On another note, Foa says ops center will be seriously compromised, and that the breach will create big headaches for Eric ... which isn't to say he's not up to it.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.