Robin Williams Recalls Time He Went Into A Sex Shop Dressed As Mrs. Doubtfire (VIDEO)

Robin Williams dropped by "Late Show" to make most of us feel really old. He was celebrating a milestone: the 20th anniversary of "Mrs. Doubtfire," one of his most iconic performances. The cross-dressing comedy co-starred Sally Field and earned more than $400 million at the worldwide box office.

According to Williams, he struggled the most with finding the right voice for the character. "Initially, I made her sound like Margaret Thatcher," he said. "That would probably scare the hell out of children." He then put on the voice and said, "Go to bed, children! I’m going to fire a cruise missile, don’t be afraid."

Williams then told a story about the time he went out in full costume in San Francisco, where the movie was filmed, and walked into a sex shop. He started asking about various items as Mrs. Doubtfire, "I could see this poor guy going, ‘Oh wow!’” Williams laughed. He said he asked for a sex toy, but the clerk wound up recognizing him and told him to leave.

Now Robin Williams is returning to the medium that first made him a household name. More than 30 years after "Mork & Mindy" wrapped its run on ABC, Williams is back with "The Crazy Ones." This time, his manic energy is balanced by his on-screen daughter, played by Sarah Michelle Gellar.

Early reviews have been mixed, but viewers will get a chance to form their own opinions when "The Crazy Ones" debuts after "The Big Bang Theory" on Thursday at 8:30 p.m. ET on CBS. Catch "Late Show with David Letterman" every weeknight at 11:35 p.m. ET on CBS.

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