Jennifer Garner Reveals the On-Set Trick Nikolaj Coster-Waldau Pulled That 'Completely Caught Me off Guard'

The Apple TV+ series The Last Thing He Told Me is based on the best-selling mystery novel by Laura Dave and is available to stream now

Jennifer Garner is spilling behind-the-scenes secrets from filming The Last Thing He Told Me.

While speaking to Entertainment Weekly ahead of the Apple TV+ show's finale on Friday, the actress, 51, shared that shooting the episode included an unexpected prank from her costar Nikolaj Coster-Waldau.

The prank took place as the actor prepared to film his character's return years after his mysterious disappearance caused his wife Hannah (Garner) to forge a relationship with her 16-year-old stepdaughter Bailey (Angourie Rice) to get answers.

"I was talking to Josh [Singer], and it seemed like a background player came and sat next to me," shared Garner. "And Josh kind of started smiling. And this person was just getting more and more comfortable next to me, and I thought, 'I don't know you.'"

Related:Jennifer Garner Runs Down Clues About Her Missing Husband in Twisty Trailer for The Last Thing He Told Me

Alberto Rodriguez/GA/The Hollywood Reporter
Alberto Rodriguez/GA/The Hollywood Reporter

Garner told the outlet that Coster-Waldau, 52, had been off-set traveling, so she was unaware he was back on set in a new costume that included a beard and hat.

"I instantly was just… I was so shocked. He was in a beard," she explained. "They were testing his look for the last scene. And he just completely, completely caught me off guard. And, you know, I cried, and I yelled at them. And then we went on."

Related:Jennifer Garner Says She 'Couldn't Stop Smiling' While Working with 'Alias' Costar Victor Garber on New Show

While Coster-Waldau joked with the outlet that pulling the prank was "a lot of fun," he shared that he also enjoyed the moment because it showed Garner's dedication to her role.

"It was an emotional reaction she had," he said. "And it was beautiful because she was very much in character. She was so invested in this relationship."

The seven-part series is based on Laura Dave's New York Times best-selling novel and is executive produced by Garner, Reese Witherspoon and Lauren Neustadter. The ensemble cast includes Aisha Tyler, Augusto Aguilera, Geoff Stults and John Harlan Kim.

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The Last Thing He Told Me is available to stream on Apple TV+.

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