Mike’s Diner in Castaic was recently visited by everyone’s favorite yellow sponge who lives in a pineapple under the sea. Yes, that’s right. SpongeBob SquarePants came to Castaic in a recent special live-action episode.

“SpongeBob’s Big Birthday Blowout,” which recently aired in two parts July 12, follows SpongeBob and Patrick’s journey on a tour of the “surface world,” where they travel to the beach, a park, an office, a fish store and finally to “The Trusty Slab” diner.

In the diner scene, actors Tom Kenny, the voice of SpongeBob, Bill Fagerbakke, the voice of Patrick, and Rodger Bumpass, the voice of Squidward, along with other notable characters, play real-life versions of the animated Bikini Bottom characters who are visiting the diner.

The episode was filmed in Mike’s Diner in March, and the diner was shut down for three days while production transformed it to look like it was underwater and shot the scene, according to Manager Sandra Hamad.

“I didn’t think anyone would recognize (the diner), because they painted everything — we had blue walls for a week,” Hamad said. “We did get to sit in while they were filming, which was fun, because they’re all the real actors that I grew up watching, so I thought it was really cool.”

Saugus resident Dan Harutunian has been going to Mike’s Diner since the 1970s when his family used to own it, which he said is why he was so happy to see it featured in the film.

“It was very cool to see it in the movie,” Harutunian said. “I thought it was cute to have a major movie like ‘SpongeBob’ shot there. They changed the place around completely for the movie, which was so cool to see.”

Mike’s Diner has been open for more than 70 years, and this isn’t its first Hollywood experience, both Harutunian and Hamad agreed. In fact, quite a few TV shows and movies have been shot there throughout the years, including “NCIS” as well as a few Netflix movies, Hamad said.

“Usually location scouts will just come in,” Hamad said. “This time they needed a diner to film in for a movie. We didn’t know which until it was chosen, and we weren’t allowed to say anything until the movie came out.”