While speaking at Muppet creator Jim Henson’s memorial service in 1990, puppeteer Frank Oz shared an unusual story with the people in attendance. During their early days at Saturday Night Live, Oz revealed, Henson once approached him with a pretty strange request. “Frank, I need to go in the dressing room with you,” said Henson. “And if you could take off all your clothes so I could take a picture of you naked,” he continued.

“Whoa,” a surprised Oz replied. Henson was insistent, and Oz, for whatever reason, proceeded to get “buck naked” for the impromptu photoshoot. Henson even told him how to pose: bent over with his hands over his genitals, facing the camera in a state of shock—which Oz noted was easy to do under the circumstances. Henson snapped some pictures, Oz got dressed, and they finished the show as planned. It wasn’t until Oz got his Christmas gift from Henson that year that he found out what the purpose of this was.

The Strange Story Behind Jim Henson’s Very NSFW Christmas Gift to Frank Oz

Oz went on to explain that Henson made him a large elaborate sculpture of Bert from Bert and Ernie (a character originally voiced by Oz). In Bert’s arms was a ledge containing all kinds of intricate details. For example, tiny photos of the people who’d help create Bert were incorporated into the design. Like Oz had been instructed to do for his photo session, they were all captured looking directly into the camera.

Eventually, Oz realized that the pupils of Bert’s eyes had been cut out. When Oz looked through the holes, he discovered that one of the nude photos Henson took of him had been placed inside of Bert’s head and was now staring back at him. Henson titled the piece Bert in Self-Contemplation.

You can listen to Oz recount the story for yourself below.

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