Mr. Poolcheck is the head lifeguard of the Gravity Falls Pool.
At an unknown point in time, Mr. Poolcheck lost his right hand in a pool filter, and has since replaced it with a prosthetic. Since the incident, he no longer underestimates the dangers of a pool. He is first seen in Dipper's story in "Bottomless Pit!" sitting at the Skull Fracture bar. When the bouncer calls for an arms against Dipper (for being a prank caller), he joins in the chase along with the rest of the bar's occupants.
In his official introduction in "The Deep End," he is Wendy's boss at the Gravity Falls Pool and later agrees to hire on Dipper. At first he takes a liking to Dipper, but comes to realize both Wendy and Dipper do not take the job of lifeguard seriously enough. Near the conclusion of the episode, he fires both Wendy (offscreen) and Dipper. He also finds out Soos has been taking the pool ducks, and he chases after him.
In "Scary-oke," Poolcheck attends the "Mystery Shack is Back" party.
Mr. Poolcheck is a somewhat unstable man, prone to violent mood swings and fits of rage. He insists on upholding the laws of the pool as though they were the most heinous of crimes, becoming furious when even the most insignificant of them is broken. He is still willing to hire people, but is often oblivious to the fact that they don't take the job nearly as seriously as he does.
Mr. Poolcheck is a tall, tan, muscular man with sharp, angular features. He has square jaw, an adam's apple, prominent cheek bones, and a low brow, giving him constant narrowed eyes. He has short blonde hair with a receding hair line. He wears a bright red polo shirt, white shorts, and white tennis shoes. He wears a gray whistle over his neck and a dab of sun lotion on his nose in typical lifeguard fashion.
- His name is a pun on "pool check", which is very fitting, as he's the pool's lifeguard.