What's next for cult hit SpongeBob Squarepants

For a simple-minded fry cook, SpongeBob Squarepants is one busy invertebrate. Not only does he have his Nickelodeon series, but ”SpongeBob” creator Stephen Hillenburg is developing a movie starring you-know-who. EW.com talked to Hillenburg about ”SpongeBob”’s surreal universe (what the heck is in those Krabby patties, anyway?), and asked everyone’s burning question: Will the little yellow guy return to TV after he becomes a movie star?

SpongeBob’s fans include Jennifer Love Hewitt, Dr. Dre, Ellen DeGeneres, Jerry Lewis, Lance Bass, and Tom Waits. Why haven’t you asked them to do star cameos?
Honestly, I deliberately avoided that. ”The Simpsons” is a tough act to follow, so I thought it was best not to do what they do. But we’ve had a few exceptions. Ernest Borgnine and Tom Conway have regularly appeared as Mermaid Man and Barnacle Boy, respectively. And Lux Interior from the Cramps has been a parrot in a party band.

You can buy everything from SpongeBob cereal to pajamas. Is there anything that SpongeBob won’t sell?
The network controls the property, so my job is just to make sure the show is really good and that’s it. It’s up to them to decline anything they feel isn’t appropriate. But I was just looking at a packet that had SpongeBob thong underwear, so it goes farther than I would imagine.

Did SpongeBob ever look like a real sea sponge instead of something you use to clean your sink?
Initially, I drew real-shaped sponges, but that didn’t click. I knew I wanted to create a character who was nerdy and kind of square, so when I drew a square sponge, everything came together. And originally his name was SpongeBoy, but there we couldn’t use that for trademark reasons.