David Harbour Struggles With A Certain Word In ‘Stranger Things’ Blooper Supercut

“The word is so funny."

One particular word kept setting David Harbour off during the filming of Netflix’s “Stranger Things.”

Harbour just couldn’t keep a straight face as police Chief Jim Hopper when it came to saying “grandma” in a scene with Finn Wolfhard (who played Mike Wheeler) and Millie Bobby Brown (Eleven).

“The word is so funny,” said Harbour, who this week made his relationship with British singer Lily Allen Insta-official.

The show’s writers room shared a supercut of the blooper on Twitter Tuesday ― a favorite gaffe from Season 3 of the sci-fi horror series’ creators, Matt and Ross Duffer.

It’s quickly becoming Twitter users’ favorite blooper reel, too.

Check out the montage here: