The 45-year-old radio personality recounted her alleged experience with Seagal on Thursday's episode of her SiriusXM show after first sharing the story in an interview with Movieline in 1998.
"A lot of people know this story," McCarthy acknowledged before recalling how she read for Seagal during an audition for "Under Siege 2. "
"I purposely wore a muumuu to the audition so the casting people would actually look at my face and watch my work."
McCarthy said she was alone in the room with Seagal, who reportedly asked her to sit next to him on a sofa.
She refused to take a seat, but admitted the actor's request was alarming.
"In my head I'm like, 'Okay, here we go. Sound the alarms, this is not a test, this is the real thing, activate all defense systems,'" the star recalled.
"But I so wanted to legitimately read for this part that I wasn't going to give up yet. So I told him, 'Listen. My agent says there's no nudity. I specifically asked her and she said no.'
"He says, 'Well, there is off-camera nudity,'" she said.
"He then says, 'I can't tell what your body looks like in that dress. Can you lower it for me?' ... He says, 'I know you must have a beautiful body under there. Can you lower it so I can see your breasts?'"
McCarthy said she went from "shock" to "sadness," and told Seagal to "go buy her Playboy video" before leaving the room.
The actor reportedly followed her out to her car and warned her not to tell anyone about the experience.
McCarthy's renewed allegations follow new sexual harassment claims against Seagal this month.
Actress Portia de Rossi said in a tweet Wednesday that Seagal once unzipped his pants in front of her at an audition.
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