04/21/2004 at 01:00 AM EDT
Speaking of baby-boomer favorites, "McHale's Navy" fans take note: Ernest Borgnine and Tim Conway, who costarred on that '60s sitcom, are reuniting for their first joint TV project in 33 years. They will lend their voices to the cartoon characters of retired superheroes Mermaidman and Barnacleboy, respectively, on an episode of Nickelodeon's "SpongeBob SquarePants." It will air this Saturday, Aug. 21, the children's cable channel said Monday. These are guest shots only.