Grace Park, Tricia Helfer, Aaron Douglas, Rekha Sharma, Michael Hogan, Michael Trucco , Battlestar Galactica
Battlestar Galactica (Fridays at 10 pm/ET, Sci Fi) is back, and the new Cylons are getting in touch with their inner robots.

Prepare for the big Cylon freakout. In last spring’s season finale of Sci Fi’s Battlestar Galactica, four of the human colonists came to the rocking, shocking realization that they’re members of the cybernetic Cylon race. In other words, they are their own worst enemies! So when BSG returns for its fourth and final season, viewers will find this quartet of undercover “Toasters” — Col. Saul Tigh (Michael Hogan), “Chief” Tyrol (Aaron Douglas), Ensign Sam Anders (Michael Trucco) and presidential aide Tory Foster (Rekha Sharma) — struggling to make sense of their new identities while staying deep in the closet.

“They’re all in this together, but there’s going to be a lot of dissension and distrust among them,” executive producer Ronald D. Moore says. “These are four people who’ve never had close relationships with one another, and now they’re trying to figure out how the hell this happened. Are they sleeper agents? What are their real backstories? And how do they handle this going forward? It results in a lot of acrimony.”

Each of the four reacts differently to this twist of fate. Tigh, the ultimate Cylon hater, “will be in big denial,” says Hogan. “This hits him so hard he goes into a whole other zone, where he buries the situation like he buries his drinking and his other vices.” Good ol’ boy Tyrol “tries not to go off the deep end by being practical about it,” Douglas notes. “He tries to make it make sense."

Tory looks for the silver lining. The character will become more politically prominent in Season 4, while her boss, Laura Roslin (Mary McDonnell), fights a relapse of cancer. “Everything has been so crappy for the humans that Tory tries to embrace being a Cylon in some way,” Sharma says. “I think she hopes [the foursome] are the evolutionary bridge between the humans and the Cylons and that they can fix everything.”

Anders has no such lofty thoughts. “For him, this is just a big pain in the ass,” says Trucco with a laugh. “Anders is a hard-core loyalist and resistance fighter, so being a Cylon goes against everything he stands for. He’s a staunch hero, but this brings out his darker side.” And it’s not the only ton o’ bricks to hit Anders. His wife, Kara “Starbuck” Thrace (Katee Sackhoff), will return to him from the “dead” this season, and there’s widespread suspicion that she, too, is a Cylon. “Anders tries to assess her without giving away his own secret,” Trucco says. “If she’s a Cylon, it’d be great to have her as his ally. But if he admits he’s a Cylon and she isn’t one, then he’s screwed.”

Eleven Cylons now have been revealed, so who is the 12th and final Cylon? Contrary to fan speculation, Moore swears it isn’t one of the show’s primary humans. Not Starbuck or President Roslin. Not Admiral Adama (Edward James Olmos) or his son, Lee (Jamie Bamber). Or even the ever-dubious, Cylon-shagging Gaius Baltar (James Callis). “Even if you guess correctly, it’s still just a guess,” Moore says. “There’s no way anyone can figure it out without knowing exactly where we’re going with the final season.”

Since much of that remains to be filmed, the cast is clueless. “We’re going along for the ride, just like the fans,” Trucco says. “We don’t even know where the four new Cylons fall in Cylon chronology. Are we predecessors? Or did we come afterward? Are we divine?”

Adds Douglas: “So far, in scripts, there are no multiple copies of us, unlike with the other Cylons, so maybe we’re one-offs. Does that mean we can die?”

And what about the humans’ quest for Earth? Moore promises that they will arrive there — uh, here — before the series wraps up. But what will they find? Dinosaurs? Ancient Greeks? George W. Bush? “We’ve never revealed our timeframe, and that’s been one of the key questions from the very beginning,” Moore says. “What is the connection between us and the humans of BSG?"

Douglas concludes, “All I know is that everything better track when all is finally revealed, because there’s nothing like a sci-fi fan scorned!”

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