Warning: This article contains spoilers for tonight's season premiere of Eureka.

Eureka, arguably Syfy’s most popular original series, returns for its fourth season tonight at 9 ET/PT. The third season was Eureka's highest-rated and most-watched ever, averaging 3.2 million total viewers per week. It was also the show’s best season ever in adults 18-49 (averaging 1.4 million per week) and adults 25-54 (1.6 million per week).

Looking to improve on those numbers, Syfy and Eureka made a Lebron-like signing, adding to the cast James Callis, best known for his Saturn Award-winning run as Dr. Gaius Baltar in Ronald Moore's reimagining of Battlestar Galactica. The British actor plays physicist Dr. Grant, a former resident of Eureka whose unexpected return is cause for concern -- not only because his reasons for leaving are shrouded in mystery, but also because of his romantic interest in Dr. Allison Blake (Salli Richardson-Whitfield). That especially doesn’t sit well with Sheriff Jack Carter (Colin Ferguson).

Co-creator and executive producer Jaime Paglia says everyone involved with Eureka is a huge fan of BSG, and he admits that landing Callis was a huge score.

“It’s an amazing accomplishment what they did with that show," Paglia explains. "It’s sort of in a category by itself. And James is the consummate actor. So for James to embrace the character that we created for him and to have him come over and be a part of our series is really exciting for all of us.”



Ferguson couldn’t agree more. Eureka’s leading man says when Battlestar Galactica and Eureka were on the same lot, Callis was one of the first and “definitely most vocal” people to support the new kid on the block.

“It’s really fitting that he’s the one who gets to come on our show and do ten episodes,” Ferguson says. “We are all really, really happy to have him. Working with James, I mean, it’s sort of preposterous how nice a man he is. He’s like the sweetest guy in the world. He just extends himself so above and beyond for everybody. So that alone is a pleasure.

“And then he comes at it [so strong]. It’s nice to get a different energy on the set because he’s such an actor. He’s always digging through the show’s history and doing his own research and coming up with different angles for things.

“So it’s really nice in a season where we are sort of reinventing or rebooting, to have someone doing all that work again and reminding you to dig in. See what you can find. So as an actor it was fantastic and as a person it was fantastic.”

And there’s the big spoiler.

In tonight’s season premiere, the residents are celebrating the founding in 1947 of Eureka, when mysteriously -- albeit in Eureka-like fashion -- the main cast is transported back in time. The overall arc of this season explores the reasons, mechanisms and resulting oddities behind the quantum leap. Both Paglia and Ferguson see Syfy’s sign off on the massive new dynamic as a signal that the network’s faith in Eureka and its science has never been stronger.

“I think that this was an opportunity to have our same town and our same characters but in new dynamics and relationships," Paglia says. "And we get to play the fun of that out for a 20-episode arc. I think for everybody here it re-energized us because it was a chance to really kind of reboot in some ways and again embrace the aspects of the show that we’ve loved and change some of the things that I wasn’t necessarily as thrilled about.”

Ferguson adds, “It was a huge sort of boon for us because it was a statement of faith by the network. It’s a monstrous thing to do. It’s a monstrous reboot to do in Season 4. So the fact that they would sign off and show their faith in Jaime and the writers and all of that stuff on that level gave us a bunch of confidence and a bunch of energy.”