"SpongeBob" voice actors Bill Fagerbakke, left, and Tom Kenny in New York on June 24. Fagerbakke, 66, came aboard after Kenny was cast. “It was the most unusual audition I’ve ever had,” he says.

Tom Kenny and Bill Fagerbakke, the voice actors behind SpongeBob Squarepants and Patrick Star, reflect on the show's wild history as it turns 25.