David Harbour loves teasing “Stranger Things” fans.

On Wednesday, the actor did an Instagram Live session, fully in costume and makeup on the set of the Netflix’s series’ new season.

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During the stream, Harbour said, “I’m here, shooting season four of our television show. I don’t think I’m supposed to be showing you these things. Who wants to hear spoilers for season four? Let me just read directly from the script.”

Suddenly, he noticed co-star Millie Bobby Brown watching the stream.

“Oh s–t!” Harbour said. “Millie! Oh, no. Millie, don’t tell Netflix, don’t tell Netflix that I’m doing Instagram Live from set. I’m just gonna read your sections of the script, Millie. I’m just gonna tell everybody what happens to Eleven this season.”

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Brown then joined in on the stream to ask Harbour what he’s doing.

“I’m so crazy,” he said. “I shouldn’t be doing this.”

“Get off of Live and go back to work!” she responded.

“I’m getting fired,” Harbour joked, but Brown said he was probably going to be getting a call from someone at Netflix.

“Stranger Things” is current in production on its fourth season.