One morning at SpongeBob's House, SpongeBob wakes up where he tells Gary that he is going to take a shower. SpongeBob thinks on trying a new shower head that is supposed to make the waterfall in a shape of bubbles. However, when SpongeBob installs the shower head, it doesn't work so he ends up trying to use actual bubbles to fix the problem. This only causes the water to clog up (due to the bubble container blocking it) and it causes the shower head to explode causing water to pour everywhere. SpongeBob panics as he remembers Mario is a plumber and calls him over. Mario arrives and asks SpongeBob what happened. SpongeBob said he was trying to use his "Automatic Bubble Water Shower Head" to make his water showers form in bubble showers and Mario says it's impossible since the bubble will just pop as soon they are forced through the holes of the shower head. Mario quickly fixes the plumbing and SpongeBob is impressed. Mario gets another call and SpongeBob asks if he can go along. Mario says yes and they both head out.
The next caller turns out to be Squidward who quickly slams the door upon SpongeBob's appearance. Mario tells Squidward he is here to fix his busted sink pipe and Squidward questions Mario on SpongeBob's appearance. Mario says that SpongeBob is only going to watch and Squidward reluctantly lets SpongeBob come in. Squidward says he has to go to work much to his disappointment and leaves. Mario then heads into Squidward's kitchen and notices the busted pipe. Mario looks at the damage and notices it's too big of a job for one person to handle. Mario remembers Squidward specifically telling him to not let SpongeBob help out but Mario says it's no other choice. Mario asks SpongeBob to hand him some pliers and SpongeBob ends up handing him Squidward's hedge trimmers not knowing what a screwdriver is. Mario accidently cuts the pipe and the water comes out even more. Mario tells SpongeBob to do nothing while he goes and gets an extra pipe. SpongeBob, wanting to help, tries to fix the plumbing on his own by clogging up the water but this only causes the water to build up and it completely destroys Squidward's house. Mario arrives back with the pipe but is shocked to see Squidward's house destroyed. SpongeBob said that at least the water stopped running and Mario says that at least Squidward doesn't have to worry about paying the bill as paying back for the house may bankrupt him.
At the Krusty Krab, Squidward is seen sleeping while Mr. Krabs yells at him for not working. Mr. Krabs asks where SpongeBob is as he is late for work and Squidward says he is with "some plumber guy". Mr. Krabs, remembering "plumbing," tells Squidward that he must clean the bathrooms and Squidward hesitates to do so. Squidward starts to mop but he slips on some water and the mop ends up in the toilet. Squidward tries to pull it out but it doesn't budge. Squidward then flushes the toilet but it only causes things to get worse and the entire bathroom starts flooding. The customers are washed out and Mr. Krabs angrily yells at Squidward for being too clumsy. Squidward tells Mr. Krabs to "hire a professional plumber" but Mr. Krabs doesn't want to due to the high cost of money. However, Mr. Krabs' cash register ends up floating out of the door and Mr. Krabs calls over Mario (and SpongeBob is still with him). Mr. Krabs is surprised to see SpongeBob but tells Mario to fix the plumbing as his money is literally washing out of the door. Squidward ends up getting sprayed out of the Krusty Krab and Mario tries to get to the problem. However, there is too much water for Mario to push through. SpongeBob, remembering he's "super absorbent," uses himself as a shield and Mario manages to fix the plumbing. Mr. Krabs is pleased saying Krabby Patties are on him and Mario says SpongeBob will make a fine plumber much to his excitement. Squidward is then seen heading back to his house but finds it destroyed. Squidward then says "I hate plumbers".