Drain Sergeant Kooperman is the overarching antagonist of Super Mario Bros. Super Show!, appearing as a major antagonist in the episode "Plumber's Academy". He is a plumbing instructor who was an obstacle in Mario and Luigi's destiny to become professional plumbers.
He is voiced by the late Harvey Atkin, who also voices King Koopa.
History
Kooperman is the plumbing instructor of the Brooklyn Plumber's Academy where Mario and Luigi attends to learn how to become plumbers, but he dislikes the Mario Bros. due to their failures.
He sets the Mario Bros. to the most difficult tasks, including the first task is carrying bathtubs up a fire escape and though Luigi is losing heart by his treatment while Mario was determined to prove their worth as plumbers. The second task is unclogging sinks in under ten seconds, which caused some gunk to splash onto Kooperman's face. Angered by this, Kooperman assigns the Mario Bros. to K.P., which involves digging a deep hole.
The final task is fitting several pipes together without wrenches in twenty minutes that Kooperman sets up for the Mario Bros.. Once the twenty minutes finishes, he tests out their work by pumping water through it, causing the pipes to collapse on the Mario Bros., sealing them inside with water flooding in. When Luigi cries out for help, Kooperman refuses to help the Mario Bros. by piling more pipes onto them stating that they will take their dream of being plumbers to their graves.
After the Mario Bros. escaping from the wall of pipes, Kooperman unclogs a woman's drain while some construction workers fix the road with fast-drying concrete. When the month's supply of "Drain-Buster" shows up at the door, Kooperman uses it for the sink, but he mistakenly picks up a bag of the worker's fast-drying concrete. After pouring it into the drain twice, the concrete causes the sink to back up and Kooperman decides to fix the problem at the manhole. While Kooperman pouring the concrete into the sewer, the worker demands to know what he is doing with their concrete, causing him to realize his mistake.
Soon, Kooperman's mistake turns into a disaster as the sewers start to overflow and the roads to be flooded, so the Mario Bros. rush in to save Brooklyn by going into the sewers with scuba gear and destroying the concrete clog with a jackhammer. At the end, the president rewards Mario with the Golden Plumber's Helper and Luigi with the Golden Wrench.
It is unknown what happened to Kooperman afterwards that everyone in Brooklyn found out that the flood was his fault, which he gets severely punished and fired from being a plumbing Instructor for causing it and for abusing the Mario Bros. by having his plumbing license revoked.
