R64: We're going on a Luigi hunt is 19th video to the Retarded64 series.
The episode begins with Mario in the foyer of Peach's Castle, asking the viewers if they've seen Luigi recently, angrily claiming that his brother owes him money. The viewer clicks on Luigi as he enters the foyer himself, and Mario immediately gives chase. Luigi runs into another hallway, shutting the door behind him, but Mario chops the door down with an axe, Shining-style. Luigi then tries to fight him off by throwing his shoes, as well as Toad, at Mario. However, Mario proceeds to go after Luigi as the two brothers make their way towards the castle garden.
Upon entering the garden, Mario finds that Luigi has disappeared. He sees SMG4 lounging around outside and demands to know if he's seen Luigi. SMG4 reluctantly asks what happened between the brothers this time, prompting Mario to contemplate how the fight started.
The episode then cuts to a flashback of about one hour prior, with Mario sitting in the park, having a picnic date with a plate of Spaghetti. Luigi suddenly comes by, driving his kart while completely intoxicated and runs over the spaghetti plate. After he crashes, Mario confronts him, furiously demanding that Luigi give him money so that he can buy more spaghetti. Luigi tries to compensate by giving him fake Monopoly money, but Mario doesn't buy it and starts the chase that has been going on since.
Back in the present, Mario is still thinking to himself, presumably not telling SMG4 what actually happened. As he snaps out of his thoughts, he continues to look around the garden for Luigi. Mario suddenly spots Luigi's hat sticking up from a group of bushes and sneaks over. However, when he tries to catch Luigi by surprise, he discovers that it is actually a small Luigi Doll with a recording of his brother's voice taunting him. Furious, Mario vows that he WILL find Luigi.
Later, Mario confronts a lounging Chain Chomp and tries to get it to pick up Luigi's scent by making it smell a pair of his brother's briefs. After a bit of encouragement, which involves Mario kicking the Chain Chomp, the beast quickly gives chase. It eventually crashes into the halls of the castle, revealing that the trail leads to Toad. Mario demands to know why he has Luigi's scent, and Toad confesses that it's because he had been rummaging through the brothers' undergarments earlier. Seeing that Mario is disgusted, Toad quickly darts off.
Mario eventually goes over to a Pet Store and asks Snoop Dogg for a new tracking dog, revealing that the Chain Chomp is still chasing after Toad. Snoop Dogg tries to offer Mario a few alternatives, such as a fowl-mouthed parrot and a pole-dancing chicken, but Mario insists on something that will help him find Luigi. Snoop Dogg then gives him a "Retard Detector," which immediately goes off the moment that Mario grabs it. Not knowing that the device is calling him the "retard," Mario believes that it knows where Luigi is and runs out of the store without paying.
Mario follows the device until he comes to a forested area on the side of the road. Seeing no site of Luigi, Mario believes that the Retard Detector is broken and angrily throws it at a nearby sign. He looks at it more closely and sees an ad for a bounty hunting service. Excited, Mario calls the number and the Sniper immediately drops in. He shows the Sniper a picture of Luigi and orders the bounty hunter to track his brother down, to which the Sniper eagerly gets out his gun.
Meanwhile, at Whomp's Fortress, it is revealed that Luigi is currently hiding in a tree. The Sniper aims at him from a high ledge, and proceeds to open fire on him. Luigi jumps out of the tree and tries to escape from the raining bullets. The Sniper's ammo eventually runs out and Luigi taunts him before taking his chance to flee. Luigi then comes across a group of rabbits hopping around and tries to blend in by donning a pair of rabbit ears. While the Sniper scopes through the crowd of rabbits, one of the creatures (which is just the Demoman in a rabbit suit) becomes infatuated with Luigi and chases him around with a desire for intimacy. Among the chaos, Luigi's rabbit ears fall off, giving his hiding spot away to the Sniper. The bounty hunter jumps down and attempts to attack Luigi, but Demoman comes to his aid and blasts the Sniper into the sky.
Over at Delfino Plaza, Mario is relaxing on the beach, fully certain that the Sniper will be able to bring the money that Luigi owes him. However, the Sniper suddenly comes down from the sky and crashes right in front of him. Finally fed up, Mario decides to take care of the problem himself, declaring "no mercy" on his brother.
Later on, Luigi continues to wander around with caution, complaining about why Mario can't understand that he doesn't have any money on him at the moment. He suddenly comes across a fashion magazine attached to a fishing rod, with Mario visibly holding the other end from behind a bush. Luigi obviously does not fall for the trap and proceeds to walk away. However, Mario proceeds to jump Luigi from behind, and the latter blacks out.
Luigi eventually wakes up to find himself tied to a chair in a dimly-lit basement. Mario confronts him, reassuring Luigi that he is not going to kill him, but rather, torture him for eternity. He then forces Luigi to face both the crude parrot and the pole-dancing chicken from the Pet Shop, overwhelming him. Luigi begs Mario to come to his senses and try to forgive him, but Mario just ignores him. However, SMG4 suddenly barges into the basement to demand what Mario is up to, revealing that he found him with the Retard Detector that Mario dropped. Deciding that he can't let SMG4 leave after finding his hideout, Mario prepares to attack him, but the latter merely sets some money on the ground to end the whole ordeal. Happy that he is finally able to buy more spaghetti, Mario leaves the basement. SMG4 follows suit after he eagerly grabs the pole-dancing chicken, which he has always wanted. As a result, both of them leave Luigi tied up, and the blooper ends with him being forced to continue hearing the parrot's profanities.