This Thursday at 8/7c, Fox’s Bones will (temporarily) go out with a bang, as the seven-year-old procedural’s perhaps most sinister villain ever is introduced.

Executive producer Stephen Nathan tells TVLine that this new baddie — named Christopher Pellant, played by Andrew Leeds (Dirt, Nip/Tuck) and described as a “genius hacktivist” — “will fundamentally change the direction of the show by the end of the season, even though he’s not going to reappear that often.”

Specifically, the EP warns, “Brennan will find herself in a situation she never thought she’d be in — and [Pellant] will be instrumental in that.”

Speaking with assorted cast members, the consensus was that this new recurring adversary will chill the Jeffersonian team, as well as viewers, to the bone.

“This guy is, I think, more diabolical than anyone we’ve dealt with before,” Tamara Taylor (aka Cam) told me. Summing up Pellant as “creepy-scary,” she says, “He’s super-smart — maybe smarter than all of us combined — he leaves riddles, and he dismembers bodies and leaves the parts all over D.C.”

Pellant’s modus operandi, Michaela Conlin (Angela) attests, “is really gross” — no small praise given the icky-gooey fare Bones regularly bubbles up  His Jan. 12 debut, in particular, “is a disturbing episode, for sure,” she says.

On the lighter, much less-gross side, Thursday’s winter finale will also unveil the living quarters that Brennan, Booth and Baby B will call home.

“We’ve been playing that [arc] through these first six [episodes] — where they can live, what they can afford — so we’re setting up and giving them that life,” says Nathan. “We’re going to go [into the break] knowing what the new threat is, and where they’re go to be living.”

And when does said break end? Though no official date has been announced by Fox, elsewhere during my one-on-one discussion with Nathan, he mentioned “the end of March” as being when Bones will be back.