William Shatner on Why He Enjoys Dropping F-Bombs: 'It's a Juicy Word'

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William Shatner is swooning over his favorite F word.

Serving as SXSW's keynote speaker in a chat with film producer Tim League on Thursday, the Senior Moment star explained why he's a fan of sprinkling the four-letter word into conversations.

While speaking about disruptive electronic gadgets and what he would do about them, the 91-year-old said, "Shut the f--- up. I understand f--- is ugly to you. But it's a juicy word."

He then turned to the sign language interpreter and said, "Shut the f--- up," before asking him to "teach us the sign language for f---," causing the audience to erupt in laughter.

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On a more serious note, Shatner used his time on the panel to recall the early days of his acting career how his dad encouraged him to stick with the art. His start, he said, happened after he went to a "basic" summer camp just outside of Montreal, Canada when he was 6 or 7.

"There was boxing but then we'd put on a play. And I made the audience cry and I thought, 'Look at that, I made them cry,'" recalled the Emmy-winning actor. "My father who had come by, said, 'My boy Bill, you made the audience cry.' Now my father is giving me love. I liked this. I think I will do it again."

Greg Doherty/Getty William Shatner

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Though Shatner was a natural at acting, he admitted his skills did not extend into the theater management world. He took on the behind-the-scenes role after graduating from McGill University.

"I was always an actor and [Canadian actress] Ruth Springford directed amateur plays I was in," said the Star Trek star. "The fateful thing, upon graduation from McGill, Springford made a summer theater. I asked to be in her summer theater."

He was ultimately rejected by the theater — but they let him be the theater manager instead. "I was the worst theater manager. I lost tickets, I lost money," admitted Shatner.

Before his first big break, Shatner revealed he served as an understudy for Christopher Plummer at the Stratford Community Theatre.

Frank Trapper/Corbis via Getty Christopher Plummer

"He was playing Henry V, so Chris Plummer who had become an acquaintance, was playing King Henry, so the director said, 'You have to understudy the role.' It was repertory theater so we rehearsed a play before we opened for a month or so," said Shatner.

"In the first week of opening the Shakespeare play Chris Plummer got ill and they came to me and said, 'Can you go on?' I said yes. I didn't know the names of the actors, I did not know where to walk but what I did know was the actor's muse had been on my shoulder and the actor's muse said to me, 'Learn the words.'"

Asked by League if he and Plummer were still friends, Shatner quipped, "I am still friends with Chris. He's dead." (Plummer died in February 2021 at age 91.)

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As for how he landed the role of Captain James Tiberius Kirk in Star Trek, which debuted in 1966, Shatner credited raw "talent."

He explained, "They made a pilot with an actor called Jeffrey Hunter. He was quite a name. They had sold the concept to NBC and presented to NBC and then there's that moment when the gods, in this case the NBC executives, decide to buy, or not to buy. They said, 'No, we aren't going to buy, but we like the idea. Rewrite and recast.' I have never heard of that happening before or since. They looked for a new captain and called me in New York. I added a little lightness [to the role] and then it sold. And that's the answer."

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The show went on for three seasons before it was canceled. Asked if it was a "failure," Shatner said, "Failure? Not quite a failure... It was a good show. It had some wonderful stories to it. Great ideas given to us by many great science-fiction writers like Isaac Asimov. Some of the ideas were marvelous."

Following the cancelation, Shatner ventured out and did summer stock theater. He said, "In those days, if you did a series, it took years before producers thought they'd want to see you in something else."

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He's also performed standup as his iconic character, Captain Kirk.

"Oh Lordy lord ... well, I thought it was very funny I was asked to do standup comedy. There is nothing more pure and innovative, and it requires genius. I thought it would be really funny to be Captain Kirk who wants to be a standup comic but he doesn't know how to do it."

Still, the response he received was less than ideal. "And there was silence," he said of the crowd's reaction. "Oh s---, this isn't going well. It was probably the worst thing that ever happened to me. When I came off the stage I slunk off and the manager looked at me and that was it."