Kate Mara’s “House of Cards” character Zoe Barnes was brutally killed off by her lover Frank Underwood (Kevin Spacey) back in Season 1, so former showrunner Beau Willimon thought it would be a great idea to have Mara make a cameo appearance in their fourth season.

In her cameo, Mara’s Barnes came back as a ghost in a dream to haunt her lover-slash-killer. Underwood’s dream involved Barnes and Peter Russo (Corey Stoll), who was another person killed off by the ruthless politician.

The three had a “bizarre” and “surreal” threesome, according to Mara. Underwood did not enjoy their sex scene, which made the scene “hilarious” to shoot.

“Beau Willimon called me and asked me to do it. He was like, ‘Just come in for one day and we'll do this really weird thing, and that'll be that,’” she shared with Digital Spy.

“I was like, ‘OK, I don't really know what this is…’ I didn't read the rest of the episode and I didn't know what was going on in the episodes before that. I didn't really want to know because I wanted to enjoy it like everybody else!” she continued.

Mara said it was always a blast shooting scenes with Spacey, and being reunited with her co-star brought back so many happy memories on the set. “It kind of felt like I'd never left. For 24 hours, I was back on the show and it was very funny and surreal,” she said.

Spacey is a well-loved personality on the set. Even Joel Kinnaman, who plays his political rival Will Conway, cannot help but gush about the actor.

“I really enjoyed the scenes I had with Kevin,” he told The Hollywood Reporter. “He's such an amazing actor and this character is something he completely embodies. It was like a sparring match and I think we both really enjoyed ourselves in that.”

“House of Cards” has such a good ensemble cast that it garnered a total of 13 Emmy nominations this year, according to the Gold Derby. Spacey got a nod for Best Lead Actor in a drama series, while his work wife Robin Wright is nominated as Best Lead Actress.

“House of Cards” Season 5 will premiere sometime in 2017. Kate Mara Kate Mara reprised her role as Zoe Barnes in one scene for “House of Cards” Season 4. Here, the actress posed in front of the camera during the Christian Dior showcase of its spring summer 2017 Cruise collection at Blenheim Palace on May 31, 2016 in Woodstock, England. Photo: Getty Images/Stuart C. Wilson