The One Tree Hill alum played Negan's wife Lucille on Sunday's season 10 finale of the hit AMC series
Hilarie Burton and Jeffrey Dean Morgan
Credit: Axelle/Bauer-Griffin/FilmMagic

Jeffrey Dean Morgan was admittedly apprehensive about his wife Hilarie Burton's guest-starring stint on The Walking Dead — though she ultimately knocked it out of the park.

"We shot all of her stuff in three or four days, I think. We never left the basement that we were in," Morgan, 54, told Entertainment Weekly. "That was a joy. I couldn't have asked for a cooler deal of working with Hilarie. I'm not going to lie, I was nervous as hell going in. I didn't know how she would be."

"I don't f--- around. I go to work," he added. "We better f---ing bring it. And it was great. That first day with her, I went home just like, 'Thank God!'"

Sunday's season 10 finale of the hit AMC series delved into the origin story of Morgan's character, Negan, and his marriage to Lucille, played by Burton, through a series of flashbacks. During the episode, Lucille died after taking her own life amid her cancer battle. She later reanimated, resulting in Negan burning down their home with her body in it.

Morgan said the real-life couple grew emotional while shooting opposite each other. "We never rehearsed. We couldn't even look at each other without, like, tearing up. It was very interesting. It was weird," he said.

"We only did one or two takes of everything that you saw. It was great, because we couldn't have done it anymore, by the way," he continued. "We were just wrecked."

Jeffrey Dean Morgan as Negan, Hilarie Burton as Lucille-The Walking Dead_Season 10, Episode 22
Credit: Josh Stringer/AMC

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Burton, for her part, said "the thing that scared me the most" about the part was transforming into a zombie.

"My biggest fear was that he was going to pull that bag off my head and I was going to be a s----y zombie and he would burst out laughing. I didn't want to ruin the scene by being a tacky zombie," the One Tree Hill alum, 38, told Entertainment Weekly. "[Morgan] actually made a phone call, and they gave me a coaching session, and they told me just to act like a drunk toddler, which is like a good vibe. You know? Just kind of wiggling your head around and chomping at stuff. We've got a toddler, so we just studied her."

Jeffrey Dean Morgan as Negan, Hilarie Burton as Lucille-The Walking Dead_Season 10, Episode 22
Credit: Josh Stringer/AMC

Burton also marveled at the "amazing" way her husband managed to play three different versions of Negan across one episode. "We were only allowed to film, like, 10 hours a day. There was no working the scene out and workshopping," she said. "He showed up for every single scene, ready to pull the trigger. I don't know anyone else who could do that. You're extraordinary. I'm proud of you."

Morgan and Burton have been married since 2019. They share son Augustus, 11, and daughter George, 3.

The Grey's Anatomy alum also opened up about the couple's dynamic between takes on The Walking Dead during a Monday appearance on Live with Kelly and Ryan.

"It was [a] thrill. It was just the coolest thing. We have done shows together but never had scenes together, and we really had scenes together in this," Morgan said. "It was so well-written and it was such a beautiful kind of story that we got to tell. She was so freaking good."

"I always wanted her to play this role, but, I'll be honest with you, I'd never seen her do anything that compared to what this was. I was nervous. I was nervous for her, and she was nervous," he continued. "She's so good. She's stupid good. I was so proud of her and we had so much fun." 

The Walking Dead became a smash hit after making its debut on AMC in 2010. The series will kick off its 11th and final season, which features a 24-episode story arc, beginning August 22.