Shatner, 91, was unmasked as Knight at the end of Wednesday's premiere, as was Hedgehog, a.k.a. comedian Eric Idle.
"I know they called my name. I took the headdress off, and I don't know anything else that transpired," Shatner tells PEOPLE of the whirlwind experience.
Performing underneath the Knight costume limited the UnXplained host's ability to see or hear on stage. "I couldn't hear the orchestra. I couldn't see anybody — the people, dancers," Shatner says. "It was bizarre."
Shatner shares why he picked a Fred Astaire selection, why he never watches his own projects and how he might've liked to sing a rap song if he moved on in the competition.
Michael Becker/FOX; Daniel Boczarski/Getty
Why did you want to go on The Masked Singer?
William Shatner: The time seemed right. I've got a number of projects. I want to get the word out, and this was such a popular, fun show to do it with. [I have] a book coming out in a couple of weeks called Boldly Go, a watch that I've designed that will be out there soon, this show I do called The UnXplained, which is on the History channel. I've got two documentaries that I'm doing — one is on me, and the other is a documentary on the performance I gave at the Kennedy Center. And an NFT that will be out there in a month or so.
Why did you pick the Knight costume?
Well, I don't remember choosing it, but it seemed like a good idea. Everything seemed like a good idea at the time, until you do it. It's like declaring war. You declare war, and then the moment you declare war, everything is different, and nothing is what you planned. I couldn't speak, couldn't hear, couldn't breathe. Like everybody else that I know who has done the show, the performance is a lot less than what you had hoped for because of the awkwardness of the wardrobe. But, at the same time, that's part of the fun of the show.
You have to watch your performance back to see how it went.
I don't know whether I can stand it. I usually don't watch my performances anywhere, let alone on a thing that probably went to hell.
You never sit down and watch any episodes of shows you've done or any of your other projects?
No, I try not to. Because I don't like the way I look. All the obvious reasons are my reasons.
How did you pick the Fred Astaire song "Puttin' on the Ritz"?
I liked the music. I liked the rhyme. I liked the rhythm. It's delightful. It's a delicious song.
Were there any other songs that if you moved on, you would've wanted to sing?
There's a lot of stuff out there that I like, even rap. It just requires learning. It's a fun show to do, because you can pick a song. They've got wonderful people to help you. Then when you put that wardrobe on, it doesn't go the way you planned it. So, the whole thing has its fun, but it's frustrations.
You have done so much in your career, but did anything you've done prepare you for this experience?
No, except I broke my shoulder about six months ago coming off a horse. So a broken shoulder and a sore arm probably helped me with this.
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Were you insulted by any of the guesses that the panel made? You got a whole range from Weird Al Yankovic to Jerry Springer.
I couldn't hear them. I have no idea. I think I heard my name or something. I wasn't sure. The original insult had long been performed. I had gotten into the costume as the original insult.
Do you have plans to do more singing following The Masked Singer?
One of the songs that I performed at Kennedy Center is called "So Fragile, So Blue," which we are making into a music video with the hope that it becomes a rallying cry like "We Are the World" about global warming.
Why is that such an important cause to you?
Because I'd like to see my children live and perhaps you stay alive. And I don't even know you.
What can audiences expect from the new episodes of The UnXplained that premiere Oct. 7?
I do a lot of personal appearances. I'm in front of an audience a lot. I'll say, "I'm doing this show called The UnXplained." I would get scattered applause. It's been on three or four years now. Now, when I'm in front of an audience and I mention The UnXplained — because it's been on Netflix — a lot of the audience applauds. So, it's my poll of how well the show is doing, and it apparently is doing very well.
Is there anything else you still want to do in your career?
Well, I'd like to keep breathing. That would be really wonderful.
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The Masked Singer airs Wednesdays at 8 p.m. ET on Fox.