The This Is Us alum guest stars as bounty hunter Jake on the Oct. 10 episode of Quantum Leap and will team up with Dr. Ben Song (Raymond Lee) and hologram helper Addison Augustine (Caitlin Bassett) on their latest time travel adventure. Not only was the role fun for the actor as a fan of the original '80s series, but also because he got to guest star alongside his wife, actress Sofia Pernas.
"It was the absolute best," Hartley said in an exclusive interview with E! News. "I don't know if I've ever laughed as much on a set. We had such a good time."
The episode follows Ben as he travels back to the '80s and leaps into the body of Jake's bounty hunter girlfriend Eva. The pair's newest target is Pernas' character, Tammy Jean, who Hartley teased "might be presenting as someone that she's not."
"Then there's a whole big twist that happens," the 45-year-old continued, "and that's all alongside Jake, my character, trying to figure out this whole proposal thing. He proposes to his fiancée."
But with Ben inside Eva's body, Jake's proposal doesn't exactly go to plan, the aftermath of which you can watch in the sneak peek clip above.
Unlike his character, Hartley's love life is running much more smoothly. The actor shared all about how he and Pernas'—who tied the knot in May 2021—off-screen chemistry lent itself to working together on set.
"Sofia's got a really great sense of humor," Hartley told E! News. "There were a couple of moments where she took some liberties, she did a little adlibbing, which allowed me to do a little adlibbing. And the characters became more and more annoyed with each other, specifically Jake becoming annoyed with her, not really the other way around, and we had a lot of fun with that."
Improvising on Quantum Leap is something Hartley said not a lot of guest stars get the chance to do. But on This Is Us, it was something that was encouraged.
"The reason you were here is because you're gonna bring something for us to the show, so please, 'Tell us, what do you want to do?'" he shared. "'Let's go. We'll play with you.' We loved that, and Quantum Leap has the same kind of vibe."
While the idea of leaping into another person like Ben does on the show doesn't sound appealing to the Hartley, there is one event in history the star would love to travel back to.
"The day the [Chicago] Bulls won their last championship with Michael Jordan," he revealed. "I'd be sitting courtside and I would watch that game, and I would love to have been there for that. That would have been amazing, his last championship. And then 'boom,' right back to me."
Quantum Leap airs Mondays at 10 p.m. on NBC.
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