Ginnifer Goodwin, Bill Paxton and Jeanne Tripplehorn Ginnifer Goodwin, Bill Paxton and Jeanne Tripplehorn

The cat's out of the bag in the fifth and final season of Big Love: Bill Henrickson (Bill Paxton), Utah's newly elected State Senator, has announced that he and his family are polygamists — and it's not sitting well with everyone.

"I don't think Bill regrets [the announcement], although I think he has underestimated the amount of animosity and persecution he faces," Paxton said at the Los Angeles premiere on January 12. "But he has to try to reform the image of plural marriage and polygamy, otherwise it will be left to guys like Alby (Matt Ross) to promote."

Bill's three wives struggle to come to terms with living out in the open for a greater cause. Barb (Jeanne Tripplehorn) turns to blasphemous activities to cope with the stressful situation, Margene (Ginnifer Goodwin) falls into depression after losing her thriving business and Nicki (Chloe Sevigny) exercises bad judgment in an attempt to protect her children. "They're all naked and vulnerable at the very beginning. They're kind of like turtles without shells," says Tripplehorn. "They've been trying to hold this secret forever and it's finally out. It really brings up a lot of emotions."

And another secret that's even bigger than their marital situation is about to come out in episode 3. "I've decided that all I can do is tell people what it's not, because it's such a big, juicy secret," teases Goodwin. "So it is not that Margene used to be a man. But it is something kind of as big." The fallout from the shocking reveal will play out in the remaining episodes of the season. "It's something that is going to cause a lot of trouble," says Goodwin. "But it's a very rewarding secret to have told, in how it brings the family together in some ways."       

The cast feels satisfied with how the season and thinks fans will get the right amount of closure and drama. "I feel really good about [the final season]," says Sevigny. "I think the fans are going to be really happy and that was all I cared about, that they tied it up in a nice bow and that they got a reaction out of fans in some kind of way. I think they're going to have some [gasp-inducing] moments." The season will culminate in a "very big family event," says Tripplehorn, who tells us her reaction to the finale was "shock and awe". "The people who have been loyal from the very beginning, I hope they're satisfied," she says. "I think it's something that will stay with them after they see it."

Season 5 of Big Love premieres January 16 on HBO.

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