On a procedural, even a character-driven procedural like FOX's "Bones," backstory is sometimes difficult to come by if you're a supporting player.

So what did John Francis Daley make of the recent revelation that his "Bones" character, Dr. Lance Sweets, was born to carnival people?

"I had to take a step back and sort of rethink my whole character," Daley jokes on a recent conference call. "No, honestly I’ve no idea what they’re intending to do with my character in terms of that, but I’m very interested to see because not many times you can say that you have a character that comes from a family of carnies."

Sweets was introduced last season as a guest star, a potential foil for Brennan and Booth, yet another way of pushing out the ongoing sexual tension between the two characters. Daley was upped to cast regular status in short order and survived a season of speculation that Sweets might be the Gormagon killer to become a valuable part of the team this season.

"I’ve played a chef and a leader, but never someone that works for something as elite as the FBI," Daley reflects. "So it was interesting to have that combination of high stakes with his still coming into maturity and have to deal with all that as a 22 year-old.  That’s something I was immediately attracted to and I heard that there was interest in having me come on as a regular. When I heard about that I was very pleased because I’d immediately gotten very attached to the cast and the crew, such an amazing group of people to work with and very rarely can you say that completely honestly these days. But everyone is just a delight."

And being a regular means revelations like learning that your mother is a carnie, which isn't the last thing we're going to discover about Sweets' past this season.

"I know that we do sort of learn a little more about his growing up in foster care and of whatever happened to him before he was adopted," Daley says. "I can’t really go into specifics because it’s ultimately speculative on my part as well. But from what I can gather from the upcoming episode I think we are going to sort of learn where he came from and what secrets he’s hidden along the way."

Thursday (Feb. 5) night's "Bones" episode features the return of the Gravedigger, one of the series' rare recurring killers. 

[Spoilers coming...]

With a killer as twisted as the Gravedigger, you know Sweets will want to get in a little psychoanalysis.

"My character helps the team find out who the Gravedigger is in this next episode where Booth gets captured. And I sort of profile, when they do find out who it is, I profile that person and help them to find information that will set Booth free," Daley teases. "And I also have a fun little session with Dr. Brennan where she basically asks me to teach her how to interrogate people in the interrogation room. So I help her detect the subtleties of human emotions and expressions and teach her the simplest things that most people already know, but because Dr. Brennan thinks in a sort of different way, it’s all new to her. I teach her when someone is being angry or sad or submissive and hilarity ensues."

In his second season on "Bones," the eternally fresh-faced Daley is still relishing the opportunity to play a grown-up, gradually aging himself up from his days on "Freaks and Geeks" and "Kitchen Confidential."

"I’m still not getting any roles for anyone’s grandfather or father, for that matter unless I have some weird Benjamin Button condition," he kids. "But, no, so far the roles that I’ve been going out for are basically my age or a little younger. I definitely still have the youthful look, which many actors are thankful for and I am as well."

Sweets' youthful air has also been central to the way Daley has played the character.

"I feel like Sweets is one of those characters where he’s very intelligent and has managed to work his way up the career ladder at an incredibly rapid pace, but at the same time he’s still 22 or 23 years old so we see traces of his youthfulness in the psychological mumbo jumbo that he’s usually spouting," he says. "So I would say that in those glimpses of his youth that is where I sort of come out as just myself. Otherwise I think that he is definitely trying to restrain that side of him and try to stay the most professional, respected person as he can be because it’s the only way he can get his colleagues to listen to him seriously."

"Bones" airs on Thursday nights at 8 p.m. on FOX.