Capt. Blue SquarePants is a retired police captain and is one of the sons of Grandma and Grandpa SquarePants, uncle of Stanley, BlackJack, SpongeBob, Larry, and Todd, and brother of Sherm and Harold. He was only seen in the episode BlackJack. During the episode, SpongeBob said he needed some help from a crime fighter like Blue to save his parents from Blackjack, but Blue told SpongeBob that he was retired from being a police captain.
Blue is very lazy, but it's probably because he is retired. He enjoys drinking Clam Tomato Chowder Juice, and listening to country music on his old record player.
Blue is shaped like a sea sponge while SpongeBob is shaped like a kitchen Sponge. Blue has holes all over his body and is light orange in color. Blue has a few yellow teeth left, wears a blue cap, and has a gray beard.