Roberto Orci, who co-produces Fox's SF series Fringe, offered SCI FI Wire potential spoilers for the second half of season one, which will wrap up the storyline of traitorous FBI agent John Scott (Mark Valley). Scott betrayed his lover and partner Olivia Dunham (Anna Torv) before perishing in the pilot, and Dunham has since been imbued with memories from Scott's perspective.

"You're going to see how the relationship with John Scott develops and what the final conclusion is on whether or not he was a good guy or a bad guy," Orci said in an interview Tuesday in Hollywood, Calif. "What it is that Olivia ultimately felt about him and his role in the world will finally be played out."

Valley will appear again before the season ends. "You'll see him again, but you will have a truly satisfactory conclusion to his story," Orci said.

As for closing the door on Valley for future seasons, Orci simply said, "Never say never."

The rest of season one will also see a shift in Massive Dynamic's role on the show. "You will plateau with a new level of understanding of who they are, but it will not be the whole picture," Orci said. "You will see that they can be as much of an ally to Olivia as a foe, and they're going to actually come clean with Olivia about some things they've been doing."

Among the episodic cases the Fringe team will investigate is a case of slug gigantism. "We have these amazing scientific consultants on the show," Orci said. "When we describe the kind of thing we wanted, they suggested, 'Why not super-sizing a common virus?'"

While the show remains on Fox's schedule for the rest of this year, Orci and his colleagues are not sitting on their laurels just yet. "We don't like to think of it as a hit yet," he said. "We like to think of it as doing well, and there's always room for improvement. We're lucky to have had time to really figure out how to do the show and really find the voice of the show and to start operating like a working machine. We're grateful for the learning curve we've had. You make a plan at the beginning, and then halfway through you think the plan's not going according to plan. Then you come out the other side with a few things different but realize if you hadn't had that plan, you really would've been dead. Now, going into the second half, it's becoming what we always thought it could be." Fringe returns with new episodes on Jan. 20 and airs Tuesdays at 9 p.m. ET/PT on Fox.