Will & Grace star Eric McCormack recently appeared on The Late Late Show With James Corden. An Emmy winner for Will & Grace, McCormack got his start in theatre.

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“I was still in high school, and I was a bus boy at this dinner theatre in Toronto called O'Neills, and the show that was on at the time was all these young people in their ’20s singing songs from Broadway. I'd seen it every night,” McCormack explained. “They had no understudies.” One night he overheard Sandra O’Neill saying one of the performers was sick. “I did that Eve thing, where I went, ‘I know the part!’”

Though she initially dismissed McCormack, she did end up calling his school to ask if he really could do the part. “I went on that night and never rehearsed and sang four songs.”

McCormack appeared on Broadway in the 2000 revival of The Music Man, as a replacement for Harold Hill, a special appearance in The Play What I Wrote, and Gore Vidal’s The Best Man in 2012.