Beau Willimon weighs in on whether Frank can function without Claire.

It's time to talk about Frank Underwood (Kevin Spacey)'s future.

Season three ended with Frank in flux. Claire (Robin Wright) left the President, who was in the fight of his life to win the Democratic nomination. On the bright side, Doug (Michael Kelly) has returned to his side.

But can Frank function without Claire?

"That's one of the big questions going into season four," showrunner Beau Willimon told The Hollywood Reporter Monday at a screening for Emmy voters in Los Angeles.

Willimon and his team are preparing to shoot season four in two months — and he's scant on details about the upcoming episodes. But there's no ignoring the big development they laid out in the season three finale, with Willimon admitting he and the team were "scared" once they realized Claire would leave Frank.

"A lot of the strength of the show is based on the strength of that marriage. But as soon as we began to explore that, we realized there was no turning back," Willimon said. "We also realized we'd laid the groundwork in the previous two seasons for this conflict between Francis and Claire, and the more we began exploring it, the more inevitable it became. And the more exciting it was for us to travel that emotional terrain."

Now that Doug is back by Frank's side, Kelly is excited about the possibility of Frank being able to use him for his dirty work.

"He's obviously far more efficient with Doug by his side," Kelly said. "I can only hope that next season it'll bring more of a 'let's get some shit done.' "

Wright, who has directed three episodes of House of Cards, said she had plans to helm more, joking that the best part of directing was that she "didn't have to act."

During a panel following the screening, Spacey earned big applause when he asked a group of security personnel guarding the stage to step to the left after audience members complained they couldn't see.

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"If someone comes down the aisle with a knife, Michael is ready. It's not the first Emmy voter he's killed," Spacey joked.

Spacey continued to get laughs by performing an impersonation of Bill Clinton expressing his love for House of Cards, and later by responding to a question about "the bisexual scene" between Claire, Frank and Meechum (Nathan Darrow) in season two.

"We don't refer to it as a bisexual scene," Spacey said. "It's a Threechum,"

Spacey also opened up about his craft, particularly the notion of playing a sometimes despicable character.

"The only way I've been able to go about the work that I do is, I don't judge the characters that I play. I try to serve the writing the best as I can," Spacey said. "I don't want to ever make a moral judgment about a character, because I'm afraid if I do that I'll wear that on my sleeve."

He added that he also doesn't confuse something he as an actor does with something his character does, noting he'll get people asking him on the street accusingly, "How could you do that?"

" 'I didn't f--king do that! My character did that. Do you not see the difference?' " Spacey said to more laughs.

Netflix has renewed House of Cards for a fourth season, to debut in 2016.