Neil Patrick Harris“>Neil Patrick Harris has different thoughts about sex scenes now than he did before he starred in CBS’s “How I Met Your Mother.” Or perhaps it’s the difference between working on the stage and working on a movie set.

The “Gone Girl” star recounted his recent experience in a sex scene for that film on TBS’s “Conan,” juxtaposing it with a nude stage scene he did years ago; a scene that happened to star one of his “How I Met Your Mother” co-stars.

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Of the new scene, with co-star Rosamund Pike, he said that he was more concerned that she “felt comfortable and didn’t feel weird.” But then he tacked on an addendum, “And make sure no one really, really saw my wang.”

He wasn’t at all concerned about that during his appearance in a stage production of John Robin Baitz’ “The Paris Letter.” Interestingly, his co-star and lover in the play was portrayed by Josh Radnor, who would go on to star with Harris in CBS’s “How I Met Your Mother.”

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Before their sitcom launched, the two played awkward lovers, each walking onto the stage fully nude. But while Harris was concerned about people seeing his “wang” on the “Gone Girl” set, he had no such concerns about it making an appearance on stage.

“We were both offstage left doing the windmill, the helicopter,” Harris said of himself and Radnor. It wasn’t horseplay so much as preparation to ensure they were putting on their best presentation.

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Now, he’s all about the tease, which he said he’s far more comfortable with than a camera taking direct aim. Maybe it has to do with the intimacy and closeness of a camera as opposed to the distance of a live audience.

In theaters now, Neil Patrick Harris and Rosamund Pike strip down for David Fincher‘s “Gone Girl,” based on the book and screenplay written by Gillian Flynn. Co-stars include Ben Affleck, Tyler Perry, Carrie Coon, Kim Dickens, Scoot McNairy and Emily Ratajkowski.

“Conan” airs weeknights at 11 p.m. ET on TBS.