This is the first half of the fourtieth episode of Curious George.
George has grown tired of playing with the same bath toys every day, so he decides to go into his room and use his box of stray stuff as toys. Much to his dismay, however, he finds that some of the items sunk to the bottom of the tub, while others floated on top of the water. He then drains all of the water, accidentally draining the "toys" in the proccess, though he manages to save a pen cap. He wonders how to get the things back, then assumes that turning the faucet on will bring them back. However, as he does this, water begins to float back up the drain.
Meanwhile, The Man with the Yellow Hat sees that water is coming up the kitchen sink, but he does not know why. George comes up and attempts to show him that this is occuring in the bathroom as well, so The Man decides to call Mr. Auger, the plumber.
When Mr. Auger arrives, he jokingly states that for once, he would like to be invited to someone's home to have a cookie before asking the Doorman where the water main shut-off valve is, to which he replies that it is downstairs and asks Hundley to show him. As Mr. Auger follows Hundley to the basement, he shows George all of the pipes and tells them of their purposes, as well as showing him the shut-off valve, which will turn the water off to everyone in the building until he turns it back on.
Back in the apartment, Mr. Auger begins searching for the clog in the bathroom sink and bathtub as George watches. Mr. Auger finally locates the clog in the pipes under the kitchen sink and removes it, which turns out to be the things George had drained down the tub earlier. When George shows Mr. Auger and The Man what had happened, the former hypothesises that after George had drained the tub, the water current carried the things through the pipes and into the kitchen, where the snake got tangled, preventing water from passing, and resulting in the water coming back up the drains. Mr. Auger points out that the things George had drained are not bath toys and reccomends that The Man buy him some real bath toys. He then reconnects the pipes he had opened and allows George to open the water valve and allow the building's residents to have water again.
Later, The Man asks George if he wants a new bath toy, to which the latter replies yes, and pushes the former out the door, promising to clear the table and wash the dishes. So, George does as he promised The Man and clears the table, dumping food into the dishwasher and putting the dishes in. When he walks off, he notices the spoon that he had forgotten and goes to put it back in. However, he notices soapy water emerging from the dishwasher, beliving that Mr. Auger had missed a clog. He then grabs his tools and attempts to fix the clog himself, repeating everything Mr. Auger had done to fix the last clog. However, he finds nothing, so he goes downstairs to the basement and opens one of the pipes, thinking that this clog had moved down here. Realizing that this is too big a job for a monkey, he decides to turn the water back on and find The Man with the Yellow Hat. However, he had forgotten to reconnect the pipes, resulting in a flood in both the apartment and the basement.
Mr. Auger then comes back, and locates the clog in the dishwasher, revealing that it was caused by George dumping food into the dishwasher and tells him not to do so and to "leave the plumbing to the professionals". The episode concludes as George takes a relaxing bath with his new bath toy, a large rubber duck, garunteed never to slip down the drain.