Neil Patrick Harris had a tart response for an overeager fan who interrupted a performance of his new Broadway show.

When a female theatergoer shouted out, "I love you, Neil," midway into his Saturday performance as the title character of "Hedwig and the Angry Inch," Harris - without breaking character - responded, "I'm doing something up here, motherf*****."

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The audience cheered, as the quip was taken all in good fun.

Harris' rep explained to Gossip Cop, "When the fan initially yelled, 'I love you, Neil,' Neil [as Hedwig] then responded, 'Who's Neil? I'm not Neil.' He then looked over at Yitzhak [played by Lena Hall] and said, 'Are you Neil? You better not be Neil.'"

That was followed by the headline-raising quote by the "How I Met Your Mother" alum.

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"It was all done in good fun, and fully in the context of the show. The audience went crazy and it really was a light-hearted moment," his rep said.

Harris, 40, stars in the revival of the cult hit about an East German transgender rocker looking for love. Now in previews, the highly improvisational show originally opened off-Broadway in 1998 and was made famous on both stage and screen by actor John Cameron Mitchell.

(Photo Credit: Bruce Glikas/Getty Images)