Brian Van Holt, Tricia Helfer Brian Van Holt, Tricia Helfer

Will humanity find a new home? Back in the early 1960s, the American public had no idea how close our country came to nuclear war with Russia. But President John F. Kennedy certainly knew the score. What if he was so freaked by the potential annihilation of mankind that he gave the order to send our best and brightest on a lifeboat into space? That's the outlandish — yet surprisingly fact-based — premise of Ascension, a three-night Syfy miniseries starring Brian Van Holt (The Bridge), Tricia Helfer (Battlestar Galactica), and Andrea Roth (Rescue Me).

"Ascension is an alternate history that's inspired by an actual U.S. military project," creator and executive producer Philip Levens (Smallville) says. "It's well-documented that JFK commissioned a study called Orion to explore the idea of using atomic bombs to send ships into space — ships that could destroy the Soviets on a moment's notice but could also be used to colonize the moon and explore our solar system." Kennedy eventually grew apprehensive and killed the project, but it remains wildly alive in Levens's mind. "This is total wish-fulfillment drama," the executive says with a laugh.

Levens's saga claims that JFK did launch an ark into space right before his assassination, a top-secret, 100-year mission to an inhabitable planet in the constellation Centaurus. The spectacular vessel, Ascension, is as tall as the Empire State Building and initially carried 350 passengers. Known as the Originals, these idealistic heroes — scientists, engineers, enlightened thinkers — were so determined to save humanity that they agreed to live in a society where many rights were revoked. Marriage can occur only if the couple is an ideal DNA match, and reproduction is dictated by computer. The miniseries takes place 51 years into the voyage — the point of no return — and communication from Earth stopped decades ago.

"For all anyone knows, we blew ourselves up," says Van Holt, who plays the ship's captain, William Denninger. "Putting several hundred people in a tin can in space is a fantastic way to explore the human condition. You can't help but ask yourself, 'How would I react? How would I behave?' There are now two generations on board that are not there by choice, and there is a lot of dissension."

Some of the survivalists — now numbering 600 — no longer believe in the mission and, with enough food and supplies to last only another 50 years or so, want to turn back before it's too late. "Others think they've been deceived," says Levens. "They fear Ascension is nothing more than a trillion-dollar boondoggle meant to line the pockets of those back home." The youngest generation is especially restless, and paranoia escalates when one of them — a rebellious teen girl — is found shot to death. But how did a gun get on the ship when no weapons were allowed?

"Even when mankind is given a second chance, we still prove to be our own worst enemy," says Roth, who portrays the ship's doctor, Juliet Bryce. "It's so interesting to play characters who are essentially stuck in 1963 — they're still watching Gidget and Beach Party movies and know nothing about Vietnam, Watergate, or 9/11 — but somehow the upheaval on board is right in line with what's been happening on Earth. We're making the same mistakes."

Through it all, Denninger and his wife, Viondra (played by Helfer), remain steadfastly loyal to the mission and are determined to keep the peace and stay in power, even if their methods are sometimes questionable.

"They're not unlike the Underwoods on House of Cards, with a little George and Martha from Who's Afraid of Virginia Woolf? thrown in," Helfer says. "Viondra was paired with William by genetics, yet she went into the marriage with an open heart, hoping to find love." Alas, there wasn't any. "There's a lot of hurt, but they stay a team," Helfer adds. "They know they're stronger together than apart." An ever-enterprising spy, Viondra regularly beds her husband's archrival, Councilman Rose (Al Sapienza), and also runs the ship's hooker service—not for profit but to gather pillow-talk intel.

If all this sounds like too much interstellar Sturm und Drang for six hours, it is. "We're already thinking about Ascension becoming a series if [the mini] does well," says Bill McGoldrick, Syfy's executive vice president of original content. "We've made a huge commitment here, creatively and financially. It would be great to get the band back together." The set of the ship alone is a budget-buster: five stories tall with a fully functioning elevator at its center.

"It's an uncertain journey, on screen and off," says Van Holt. "Stories this big and thought-provoking, with so many crazy turns, just don't come along often. It'll be such a bummer if we don't get to go on!"

Ascension airs Monday through Wednesday, Dec. 15-17 at 9/8c on Syfy.

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