SpongeBob SquarePants: Season 0, Episode 15

0 - 15: The Clash of Triton

It's Neptune's five thousandth birthday and his wife throws him a lavish party at the Krusty Krab, but Neptune is depressed because he can't help but think of his son, Triton, that he imprisoned many years ago. SpongeBob frees Triton, but it turns out he has made a huge mistake.