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As the "How I Met Your Mother" cast prepares for its show's night's series finale on March 31, they made an appearance on "Inside the Actor's Studio" where a fan asked if Neil Patrick Harris and Jason Segel for a special favor.

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After the pair briefly sang the Inspector Javier and Jean Valjean duet, the "Confrontation," on the "Megan Mullally Show" in 2006, the fan asked if they would reprise the performance. With almost no hesitation, they broke into the famous Broadway show tune.

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Perfectly executing the wordy duet, the duo brought the house down, as the happy audience gave them a standing ovation.

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The series finale of "How I Met Your Mother" airs Monday, March 31, at 8 p.m. ET on CBS.


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