SMG4: The Super Mario Stupid Show is a blooper uploaded on March 31, 2018.
After saving Princess Peach yet again, Mario decides to fetch some spaghetti from the fridge. SMG4 suddenly bursts out of his room after finding a solution to his plan of getting himself a "bajillion" views. He then tells Mario his plan and forces him into a van he's driving by threatening to shoot him.
Mario notices Luigi, seeing that he isn't the only one to be in with SMG4, who is rather enthusiastic about his plan. When the three arrive at a film studio, Luigi is afraid that SMG4 will try to torture the brothers. SMG4 proves him wrong and reveals it is the Super Mario Bros. Super Show.
He then changes the Mario Bros.' wardrobes (only having the colors of their shirts and overalls inverted, and when Luigi questioned this, SMG4 tells him to shut up) and introduces the Paisano brothers: Danny Wells (Luigi) and Lou Albano (Mario). He places them in front a green screen so filming of the show can begin.
Lou tells SMG4 that he doesn't know what to do since he didn't give them a script, but he ignores them, so he and Danny improvise by dancing. At one point Mario rams everybody (minus Luigi, who had left the stage) with his kart, which doesn't bother SMG4 at all as they capped it at one minute, preventing them from receiving a copyright strike.
The intro finally begins with Danny telling Lou poor jokes about spaghetti, a pipe bomb, and hammer, when suddenly they hear banging noises coming from upstairs. At first they don't mind it, but start to get annoyed after it repeats over and over again. The source of the noise is revealed to be Mario.
Danny says Mario is being rude and impatient. Angered, Mario throws a rock at Lou, angering him to the point where he throws the pipe bomb into the hole in the ceiling, where it lands in front of Luigi and explodes in his face. SMG4 then moves on into the cartoon segment, much to the surprise of the Paisanos.
The cartoon segment starts with the Mario Bros. reaching the castle of the actor who portrays Bowser (named King Koopa in this show) who held Peach (another actor) captive, much to Mario's chagrin, as he just saved her this morning.
Mario then calls Koopa a "big, fat, stinky green jerk" upsetting Koopa. But he goes along anyway, telling the Bros. that they'll never get to the top, by adding Chain Chomps and spike traps. When Koopa turns his back, however, Mario and Luigi somehow reach the top easily, scaring him to the point where he accidentally throws the Peach actor to the ground. While Luigi goes to check on her, Mario easily beats Koopa by kicking him off the roof, causing him to land on top of Peach.
Meanwhile, Lou and Danny are chatting while drinking coffee. Unfortunately, the Peach and Koopa actors fall from the ceiling and on top of them. Having enough of the Mario Bros.' antics, Lou and Danny confront them while in the middle of bragging about their "success".
The two accuse the Bros. of ruining the show on purpose. Mario, as usual, doesn't care and responds by taunting them. Resulting in a brawl between the two pairs of siblings. Luigi initially stays out of the violence, but then he sees Danny beating up Mario while Lou holds him in a full-nelson. Angered upon seeing his brother pummeled, Luigi uses his Green Missile attack on the Paisanos, sending them (and Mario) crashing into the theater. While Mario and Lou battle each other, Luigi tries to stay away from Danny.
Mario manages to overpower Lou and even throws a Poison Mushroom at him. Lou then uses a Fire Flower to attack Mario while shouting "KAMEHAMEHA!", but he dodges them all and uses a P Switch to turn the blocks Lou is standing into coins causing him to fall.
Lou then tosses a shell at Mario that gets stuck on his head and compresses it. Mario retaliates by throwing a Yoshi Egg at Lou, causing him to get propelled into a monitor backstage and his head stuck in it. The monitor plays infomercials of the SMBSS and even an anti-drug PSA featuring Albano as Mario.
Meanwhile, Luigi is still trying to keep his distance from Danny by climbing onto the curtains. Danny orders him to get down from there, but Luigi refuses and keeps climbing. Meanwhile, Lou manages to get the monitor off his head and tackles Mario, hitting a lever in the process. This causes a spotlight to fall from the catwalk, which releases sparks that start a fire and destroy the stage, leaving everyone seriously injured.
SMG4, who was recording every moment of the brawl, thinks it's awesome and thanks everyone before leaving to upload the footage onto YouTube. The exhausted Mario Bros. decide to go home, and the episode ends with Mario kicking Lou in the groin as payback.