With rumors rife that Callen (Chris O'Donnell) was finally going to find love this season in "NCIS Los Angeles", it would seem that he ends his life as a lone wolf, but it won't be because of a new girlfriend.

After the episode entitled "Glasnost," some of Callen's questions about his family were answered when it turned out that the case of the poisoned woman he was working on involved his half sister. He also had to deal with his father Garrison (Daniel J. Travanti) about the victim.

It also turned out that Callen's dad wasn't the only family he had left as his dead half sister had a daughter. With father and son coming to an agreement that there should be no more family secrets floating around, it seems that Garrison's appearance won't be a one-off.

"I know we're going to see more of Garrison this season. We haven't really gotten into it yet. I know that for part of the time, he is still hanging around Los Angeles, and so there is interaction [between them], but we haven't explored that completely. But yeah, here's a guy who, his family is effectively Sam Hanna's and the group he works with at work, and suddenly he has actual family, like blood family - well, partial blood family - that he didn't know about. And I think there's going to be a lot of opportunities there for him. I think it will affect him in a lot of ways. Maybe this will take him out of his shell a little bit," explained O'Donnell.

Meanwhile, the team is expected to make some headway into their investigation on the mole, and their efforts will end up revealing two possible suspects.

"A new lead in the ongoing mole investigation is uncovered after two men disguised as sheriff's deputies are killed in front of Callen's home by an unknown female assailant. Meanwhile, Nell visits a prison to interview an inmate who is withholding information on the department's leak," read the synopsis for the upcoming episode.

Episode 10 of "NCIS: Los Angeles" season 8 — entitled "Sirens" — will air on Sunday, Nov. 27, at 8 p.m. EST on CBS.