As if it isn't rude enough to take a photo during a Broadway theater production, the least a person could do is turn off the flash.

An audience member watching a recent performance of "Frankie and Johnny in the Clair de Lune" snapped a flash photo of Audra McDonald and Michael Shannon while they were nude onstage in a simulated sex scene, eliciting a firm reaction from McDonald after the curtain call.

"To whoever it was in the audience that took a flash photo during our nude scene today: Not cool," the five-time Tony winner tweeted. "Not cool at all."

To whoever it was in the audience that took a flash photo during our nude scene today: Not cool. Not cool at all. — Audra McDonald (@AudraEqualityMc) July 21, 2019

Taking photos during Broadway shows is always prohibited, and when audience members are caught in the act, security usually requires them to delete the image on the spot.

While Shannon has appeared nude onstage in other live productions, this show marked veteran actor McDonald's first experience doing so.

"This is my first time, so I was scared," she told Page Six in May. "Once the show is going, you don’t think about it, you are playing the characters. It’s an important part of the story."

The incident comes just days before the acclaimed production ends its limited run.