Wilmer Valderrama Recalls ‘Friendly Rivalry’ With Ashton Kutcher While Filming ‘That ’70s Show’

Wilmer Valderrama and Ashton Kutcher got a little competitive while filming That '70s Show.

Valderrama, 44, reflected on his childhood, career and more in his new memoir, An American Story: Everyone's Invited , published Tuesday, September 17. After diving into how he landed the role of Fez — Valderrama went in for four auditions before officially being cast — the actor shed light on the dynamic behind the scenes of the sitcom.

"Ashton was far more intelligent in real life than the character he played, and he was far more serious about the craft of acting than it appeared," he wrote of Kutcher, 46, who played the "naive jock" Kelso.

Valderrama appreciated that Kutcher "always came to set extremely prepared, just like I did," and confessed that the duo had fun challenging each other.

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"He and I soon developed a friendly rivalry to see who could get the biggest laughs from the audience on the first take," Valderrama wrote, explaining that "the laugh is always bigger" the first time around. "If you mess up on the first take and try for a huge laugh on the second, the joke never lands as powerfully. If you need to do a third or fourth take, you might as well forget it."

Kutcher and Valderrama even gave themselves a nickname — the "two-takers" — while filming the series, "meaning we'd always try to land the first perfectly, then do the second take just for fun."

That '70s Show premiered in 1998 and aired for eight seasons , ending in 2006. When Valderrama was first sent to audition for the series, which followed the lives of six friends in Wisconsin in the '70s, it was titled Teenage Wasteland .

"I didn't put much stock into the show at first," he wrote in his book. "I vowed to give it my all, just like everything else. But after you've been auditioning for a few years without much success, you learn not to get your hopes up."

Valderrama faced "fierce" competition throughout the process, and he recalled seeing "a tall, skinny kid with a shock of dark hair" at his first audition. "The name sounded weird, starting with a T but rhyming with gopher. ... Tofu , maybe?" he quipped.

He was, of course, referring to Topher Grace , who went on to star as Eric Forman and became "the anchor of the show." Valderrama called Grace "a fantastic actor," writing that his respect "grew for him" the more they worked together.

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Mila Kunis , Laura Prepon , Danny Masterson , Debra Jo Rupp and Kurtwood Smith rounded out the ensemble cast, and Valderrama sang each of their praises individually in his memoir. He gushed over his "beautiful connection" with Prepon, 44, who "became like a sister," as did Kunis, 41. The entire cast became like a close-knit family.

"It seemed the more we bonded in real life and bulls---ted between takes, the funnier the show became. ... We laughed. We joked. We pranked each other. ... As costars, we became each other's No. 1 fans," Valderrama wrote.

Despite their love for one another — and for their characters — Valderrama and his castmates knew the series eventually had to come to an end. "We couldn't stay teenagers forever," he acknowledged, noting that they "all grew tired" as the seasons continued.

When the crew gathered one last time to film the final episode in 2006, the tears were flowing. Valderrama and his costars, however, weren't ready to say goodbye yet. "For the next 10 days in a row, we all went to lunch together," he wrote, adding that he'll "forever be grateful" for That '70s Show catapulting his career.

An American Story: Everyone's Invited is available now.