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In The Super Mario Bros. Super Show! live-action segment "Plumbers of the Year", the Imperial Poobah appeared at the apartment of Mario and Luigi, looking for Mario and Luigi. Shocked that the Imperial Poobah was at their home, Mario and Luigi, after reciting an oath and bowing, were told by the Imperial Poobah to rise. After doing as the Imperial Poobah instructed, Mario and Luigi asked the Imperial Poobah what he was doing in their home, only for Mario and Luigi to get the response from the Imperial Poobah that he was there to honor Mario and Luigi with the title of Plumbers of the Year.
After announcing this, the Imperial Poobah proceeded to tell Mario and Luigi that before he could give them the Plumbers of the Year trophy, he would have to conduct the Imperial Investigation, a routine check to see if Mario and Luigi were worthy to become Plumbers of the Year. After stating this, the Imperial Poobah went on to say that Mario and Luigi had nothing to worry about if they were truly worthy of being Plumbers of the Year and went on to continue saying "Nothing to worry about" over and over again, as if in a trance. As the Imperial Poobah continued to say the same words over and over again, Luigi began to slap him on the cheek, trying to get the Imperial Poobah back to normal.
Later, after inspecting the plumbing of Mario Brothers Plumbing, the Imperial Poobah congratulates Mario and Luigi on having perfectly flawless plumbing; directly after the Imperial Poobah says this though, a nearby pipe began to leak water and steam. As water and steam flowed from this pipe, the Imperial Poobah said that this changed everything, crumpled Mario and Luigi's inspection paper and told them that maybe they didn't have what it took to become Plumbers of the Year. Luigi, frantic, began trying to convince the Imperial Poobah that the leaking pipe could easily be fixed.
After, as Luigi tried to fix the leaking pipe, the Imperial Poobah watched him, stating that there was no way that the pipe could be fixed. Despite the Imperial Poobah's objections, Luigi continued to try to fix the leaking pipe and proceeded to tell Mario to get him some leftover pizza for him. As the Imperial Poobah looked onward, Mario grabbed an extra-cheese from a fridge and gave it to Luigi, who used the cheese on the pizza to fix the leaking pipe, which, surprisingly, fixed the pipe.
Amazed at Mario and Luigi's inventiveness in plumbing, the Imperial Poobah decided to crown them as the Plumbers of the Year and after a lengthy speech, officially gave Mario and Luigi the title of Plumbers of the Year and also told Mario and Luigi that they would receive some steak knifes, a pair of dice and hand choppers in the mail in six to eight weeks. After thanking the Imperial Poobah for giving them the title of Plumbers of the Year though, Mario, Luigi and the Imperial Poobah could only watch as several nearby pipes burst, unleashing water and steam.
As Mario and Luigi attempted to repair these leaking pipes, the Imperial Poobah, deciding to help Mario and Luigi with their predicament, grabbed a nearby telephone and told whoever was on the other end of it to send over several pizzas with extra cheese on them.