We open on a makeshift office in the cramped corner of an old garage. Two of the three bays are lined with shelves stocked with plumbing supplies. A faded sign affixed to the desk says “Super Cheap Plumbing.” Taped beneath it is a hand-written sign: “& Paranormal Investigators.” A squat mustachioed man in khakis and a stained undershirt is sorting through paperwork when the phone rings. He calls for his brother to answer it.

“Luigi! Phone!”

A slender man emerges from beneath a covered vehicle, oil on his blue-jean overalls. He rushes to answer the phone. “Super Cheap. This is Luigi. What? Wow! We’ll be right over!” Luigi hangs up and shakes his brother. “This woman says a turtle crawled out of the sewer outside of her apartment. It’s walking on its hind legs, like a person!”

“Yeah? Does it have a sword and a bandana?”

“I didn’t ask. Should I call her back?”

“No! And we’re not taking your paranormal cases. Crazy people don’t have money. Besides, a two-legged turtle isn’t even paranormal.”

“It’s not normal either, and I assume the turtle has all four legs. It’s just choosing to walk on two.”

“And we’re choosing to offer plumbing services.” Mario hands Luigi a slip of paper.

“Did we win the restaurant bid?”

“No.”

“Even with the free exorcism coupon?”

Mario shrugs. “And the cheapest bid. I guess some people don’t like saving money.”

“The problem is our image. We need matching uniforms, and maybe a brand without “cheap” in the name.”

“The problem is your shoddy work. If you took more pride in the job and weren’t distracted by ghosts and aliens and that stupid racecar that will never work, we’d have more loyal customers. New uniforms and new signs. All that, like our regular bills, requires money. You know where to find that?”

“No.”

“I do.” Mario taps the paper in Luigi’s hand. “In this clogged drain. Now go.”

Clearly disappointed, Luigi takes the paper, loads up the van, and drives to the plumbing job. He completes the job, all the while trying to sell his paranormal services. As he leaves he spots a turtle walking the street on two legs and he follows it back to a sewer entrance. Staying in the shadows he continues stalking the turtle through massive sewer pipes until he witnesses a gathering of hundreds of turtles, walking mushroom goombas, and masked figures in red robes.

“Super weird!” Luigi says and excitedly pulls out his phone. Distracted by his own recording, he inadvertently calls the attention of a nearby shy guy, and Luigi flees in fear.

Back at the office, Mario is checking the time. His brother has been gone awhile and isn’t answering his phone. Mario is looking over piles of paperwork on his desk when the phone rings again. When he searches to find the phone he sees an old picture of him and his brother with their father in front of their plumbing van. The van was new then and everyone was younger and happier. Mario finds the phone and answers.

Luigi rushes in and sits at the computer, pulling up the video he posted online. He encourages his brother to get off the phone and watch. Mario apologizes to the caller and hangs up, watching stoically as Luigi shares his exciting video. It’s poor quality, but the mysterious creatures are there. When it ends, Luigi is all smiles. Mario is not.

“That’s what you’ve been doing?” asks Mario. “Making fake monster movies?”

“It’s not fake! Look!” Luigi rolls up his pant leg to show a mark. “One bit me! Isn’t that great?”

“Not when we can’t afford health insurance! And we can’t afford that because you keep messing up the jobs. That phone call was from the woman whose sink you were supposed to have fixed.”

Luigi tilts his head. “And she was calling to say what good work I did?”

“No. The sink, like your brain, is still clogged. Now you have to go unclog it again, except now it’s free of charge!”

“But this is important Mario!”

“So is this business! Our father’s business, remember?”

“Pop loved plumbing, Mario. You love it. I want to do something bigger.”

“And chasing ghosts is bigger? Will that bring you the fame and fortune you want?”

“I don’t know. Maybe. It’s gotta be better than this. Don’t you ever get bored with plumbing? Don’t you sometimes just feel stuck?”

“I do. You know what else feels stuck?” Mario holds out a slip of paper.

Luigi takes it. “That woman’s sink. Got it.”

We cut to the apartment above the garage. That night Luigi checks his online video to see it has very few views and the comments are all negative. He is discouraged and his leg hurts. He falls asleep, restless. In the morning he comes down to the office to see Mario in a great mood.

“We got it!” Mario says. “Triple A plumbing dropped the restaurant contract. It’s ours!”

“That’s great,” say Luigi, completely devoid of enthusiasm.

“6 sitters, 2 standers, and 4 sinks. This is the job that turns things around, brother. Get out to the site right away and meet with the client.”

Luigi nods and goes to the van, but collides with a woman in a hooded cape. She has seen his video and wants to know where he filmed it. Luigi dismisses her, but she’s persistent and when Luigi hobbles toward the van she asks how he got injured. When he tells her he was bit, she asks him to show her. When he does, she rubs some mysterious goo on it and it heals.

“What is that stuff?”

“Home remedy,” she says. “Mostly mushrooms.”

“Who are you?” asks Luigi.

Peach is riding in the Mario plumbing van, explaining who she is and what the monsters are. She is from a different world, one that has been captured by the terrible Bowser and his minions, the same minions that Luigi spotted in the sewers. He drives her to the location and they see the sewers are changing.

The pipes are large and green and plants with teeth are growing from the walls. When they find the turtles, there are hundreds more, an army. A small egg-shaped orb is glowing in the center of an open room where many of the green pipes converge. Another turtle emerges from it while the others are performing a dance. As the minions dance, the org grows larger. Luigi is recording it all, but Peach pulls him away.

She tells Luigi that they have to stop the minions and close the orb before Bowser comes through, but she can’t do it alone. Luigi calls his brother and says they need to talk.

At the office, Luigi and Peach explain everything. Luigi, once again, shares the video he has recorded, noting to himself that there are a lot more views on this one. Mario is clearly enamored of Peach but is furious that his brother bailed on the restaurant job. He says they’re both insane and fires Luigi. Peach and Luigi decide to go it alone.

Luigi is in the sewer again, shouting at the minions. When they chase after him, Peach slinks up to the orb and begins her own chant and movement, but some lingering minions spot her and she fights them off, all the while continuing her chant. Just as the orb is about the close, Bowser’s hand slips through the portal and pulls her in. Luigi, double-backing through the pipes, sees it happen. He records his farewell, uploads his video and jumps through after her.

When night comes and Mario’s calls to Luigi go unanswered, he is clearly worried. He checks Luigi’s room, a showcase of paranormal-related tokens and collectibles, then goes downstairs to see a package has arrived. He takes it inside and sits at the computer, trying to figure out how to return the package. He prints out a return slip, then looks at Luigi’s youtube page and his latest video. He’s flabbergasted. Mario grabs the package and his tools and calls a cab. When he reaches the sewers the orb is back to its former size. Mario begins altering pipes and valves and routes water to converge on the orb, flooding all the minions back through. When the coast is mostly clear, he turns off the water and sees a red robe and mask that had parted ways with their former owner. Mario dons the outfit and swims into the portal.

He appears in a flooded room. The minions are wet and confused. Dressed as a shy guy, Mario discovers he is in a vast castle, pools of lava swirling throughout, fueling engines which appear to keep the castle floating in the sky. He eventually finds a prison where Luigi is kept and rescues his brother. Luigi apologizes for being such a fool and Mario apologizes for not listening sooner. Luigi states that Peach is being held captive somewhere else in the castle and they need to find her when the brothers are spotted. Before they rush to fight and find Peach, Mario hands Luigi the package he brought from their world. Inside are new uniforms, customized for each brother.

“I ordered them when we got the restaurant job.”

“Does this mean I’m still employed?”

“Of course. You’re my brother. Now let’s go rescue the girl.”

There are scenes of fighting and obstacle jumping as they make their way to Peach. She’s in a gilded cage in a room with various treasures, glowing flowers and mushrooms and stars. The brothers knock out the guards and open her cage. Peach thanks them and tells them the treasures are from her world, special tokens that can be used to grant super powers, and they’ll need them to defeat Bowser. Mario says he came for his brother and her, but fighting a big bad wasn’t in his agenda. He wants to go home. She tells him that if they don’t stop Bowser, their world will end up just like hers. Mario agrees to fight.

Another series of fights takes them to Bowser where Luigi, Peach, and Mario are all defeated. Then each uses a super power and clobbers Bowser, sending him into the lava. Mario and Peach have a tender moment but Bowser bursts from the lava and chases them back through the castle. Mario says he has an idea but it means saying goodbye. Peach kisses the brothers on the cheek and Bowser, still glowing red hot, chases them back to the portal room where the Mario brothers jump inside. Peach stays behind and is captured again.

The brothers are back in the sewers where they start working on pipes again.

“Who thought plumbers would be the ones to save the planet?” asked Luigi.

“Pop always said we’re number one,” jokes Mario. “And number two.”

He turns a valve and a powerful force of water fires directly into the orb. On the other side minions are thrown into the walls. Jets of water disperse down castle tunnels, hardening the lava and stopping the engines. Bowser is caught in the flood and turns to igneous rock. The floating castle falls to the ground and Peach eats a star before impact. The glowing orb closes on both sides and Mario turns off the valve.

A few days later, Luigi runs into the office shouting for his brother.

Mario holds up his hand. “I know. I saw. Your videos of our escapade are a massive success and now you’re off to start your own paranormal investigation company.”

“No,” says Luigi. “The new sign came in.” He holds up a tiny sign for his brother. “It’s all I could afford.”

Mario smiles and says it’s perfect, then adheres the small sign to the one on the desk. Where it said “Super Cheap Plumbing” the new sign covers the word “cheap.” Mario and Luigi read the sign together: “Super Mario Brothers Plumbing.”