The first guest stars to appear on the show were actors Ernest Borgnine and Tim Conway, reuniting for their first joint TV project in 33 years since the 1960s sitcom McHale's Navy. They appeared as SpongeBob's favorite superheroes, Mermaid Man and Barnacle Boy, respectively. Hillenburg and Derek Drymon, the show's creative director, enjoyed the actors' roles in McHale's Navy, and they already wanted the two to provide the voices of Mermaid Man and Barnacle Boy when they were voice casting. Hillenburg and Drymon directly approached Borgnine and Conway, and the actors both accepted. When coming up for the right voice of Mermaid Man, Borgnine cracked his voice by mistake when he was saying "evil!" He said, "By golly! We started something... and we kept [the voice] in." Rock band Ghastly Ones were the first guest stars to appear as themselves, appearing to perform the song "SpongeBob ScaredyPants" in the first-season episode "Scaredy Pants." Their song was then released in the album SpongeBob SquarePants: Original Theme Highlights in 2001. Actors Jim Jarmusch and John Lurie were the first guest stars to appear in live-action. They appeared as themselves in the first-season episode "Hooky" via stock footage from the television program Fishing with John. According to episode writer Vincent Waller, "Someone made us aware of the footage, and they graciously let us use it." The crew planned to film live-action scenes; however, "the Jarmusch and Lurie addition was a very nice surprise."
