The clip in question shows Allen, who starred on the sitcom as Tim Taylor, dressed in a kilt. In response, Richardson, who played Allen's wife, Jill, jokes, "Hangs long, I just wish it was shorter."
As the studio audience laughs at the scripted antics, Allen, facing Richardson with his back to the camera, lifts the kilt. Richardson's jaw drops in shock as she and Allen laugh and the audience cheers.
"People ask me what was under the kilt when he flashed me, he was well dressed under there," Richardson tells ET. "I was just shocked that he lifted the kilt, not by a man in boxer shorts."
The clip resurfaced following Pamela Anderson's memoir claim that Allen flashed her on the set of the '90s sitcom. In Love, Pamela, Anderson, who played Lisa the Tool Girl on the show's first two seasons, alleges that the moment happened on her first day of work, when she was 23.
"I walked out of my dressing room, and Tim was in the hallway in his robe," Anderson writes, according to an excerpt published by Variety. "He opened his robe and flashed me quickly -- completely naked underneath. He said it was only fair, because he had seen me naked. Now we’re even. I laughed uncomfortably."
Allen, who was 37 at the time of the alleged incident, denied Anderson's claim, telling ET in a statement, "No, it never happened. I would never do such a thing."
ET spoke to Richardson in 2020, when she reflected on her chemistry with Allen on Home Improvement.
"Immediately, I loved him," Richardson said.
The actress enjoyed the feedback she got from fans of the beloved show, which ran from 1991-1999 on ABC.
"The primary thing I saw the most in the mail was, 'Are you looking through our windows? The things you and Tim fight about are just like our family,'" Richardson recalled. "Or, 'I get it, I have three sons too,' or, 'This is so freaky, because it's just like our family!'"
"It was very gratifying to me, because Tim and I worked so hard," she added.
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