The episode begins with Gumball combing his hair and pulling his face upwards, running into the kitchen, and haphazardly preparing a fancy-looking sandwich for dinner. As he begins throwing rose petals leading to the house's entrance, Darwin walks out and asks if Penny is coming over; after some slight miscommunications, he reveals that it is actually Alan who is coming over for dinner. Darwin correctly surmises it to be some sort of apology for Gumball's repeated, unwarranted aggression towards the poor balloon, though true to Gumball, even the apology is not without abrasiveness.
Before Alan is able to arrive, though, Gumball gets a phone call from the Keanes revealing that Jessica is sick. Gumball briefly celebrates the misfortune, though when he soon becomes angry upon seeing a photo Alan posted on Elmore Plus revealing his family to have driven past their house, ready for "an awesome day out." Declaring Alan a traitor, Gumball and Darwin set out to get revenge by following them to Joyful Burger.
They try to catch Alan in the act, but what follows is a fruitless goose chase, with Gumball and Darwin chasing the Keanes around town from Joyful Burger, to Elmore Cinema, and to the park, but never arriving in time to confront them, all while wrecking havoc along the way. With all hope seeming lost, they begin to sulk and head home. However, Gumball snaps back into it upon seeing the Keanes drive by and follows them in hot pursuit, finally catching up to them at the hospital.
Gumball and Darwin burst into the hospital room to confront Alan, where he reveals the truth: he and his father simply wanted to give his mother an enjoyable day to put her at ease for her flatulum transplant. Feeling ashamed, the two decide to make it up to Alan by performing the surgery themselves, putting Alan on anesthetics before he can protest.
The surgery ultimately turns out not to be as simple as they originally thought, with Alan's organs being made of air and thus invisible. In the midst of trying to remove the flatulum, Darwin accidentally causes Alan to deflate, sending his organs flying all over the place. He freaks out and tries to give Alan CPR through his balloon knot to little success, but right as Alan is about to completely deflate, Gumball sticks his finger in Alan, averting the crisis.
Alan wakes up to find that the surgery was a success. Unfortunately, a side effect of the surgery causes Jessica to talk out of her backside. Alan complains, prompting Gumball to go off on a rant about how nothing is good enough for him, ending the episode.
The fourth wall is broken when it is revealed that the Pupulus (such as the Robinsons) are controlled by puppeteers as shown in the diagram where a skeletal figure of a hand is illustrated in Rocky's anatomy.
In Gumball's ElmorePlus Photos and Videos, one photo is from "The Banana" and in the videos section, a frame from "The Pressure" is seen.
The anatomical diagrams of an Honest Person and Liar from "The Sock" reappear on the walls of the hospital room.
The way Gumball cooks dinner is similar to such shown on the YouTube comedy channel HowToBasic's videos.
The Melted Cheese Guy making his one-liner with his sunglasses is a reference to the opening scenes of CSI: Miami, where the character Lt. Horatio Caine delivers his one-liners before doing the same.
The way the characters (except Julius) explode when Gumball runs into them while he chases Alan in super speed is a reference to the Metroid series when the main character gets an ability with the same feature.
In the Polish version of this episode, Gumball asks, "Ktoś coś?" (loose translation: "Anybody anything?"), which is very popular modern Polish phrase used on Internet forums and Facebook trading groups.
The music that plays in the scene when Gumball and Darwin are "performing surgery" (while actually making a sandwich) and the fact that one of the "surgeons" lost his watch are both references to the Surgeon Simulator game.
In Gumball's first flashback, Masami, Leslie and Darwin were behind Gumball. In the second flashback, Carmen replaced Masami in the scene, trying to hold Gumball from Alan.
In Gumball's first flashback, he said that he bought fingerless gloves, but the package clearly shows that they are not fingerless.
When Gumball and Darwin are viewing a photo of Alan's family in a car passing by the Wattersons' house, it is shown in the background that they are viewing the photo before it was published on Elmore Plus.
When Alan and his parents go inside the elevator, Dexter's mustache is missing.
When Darwin gives Alan CPR, he makes a flatulence sound each time he pounds him. But once Darwin stops, the sound continues for two more seconds.
Gumball and Darwin dig the floor of the hospital even though they are not on the ground floor.
It should have been impossible for Gumball to pop Alan's uncle since he is a foil balloon.
[The episode starts in the Wattersons' house, as Gumball combs his hair and pulls up the skin of his face with a hair clip to force a smile; he prepares a fancy-looking sandwich in the kitchen, by adding several carrots, marshmallows, sushi, and other ingredients for the fancy sandwich. He then throws the sandwich in the oven, then less than two seconds, he takes it out of the oven. He sets the dinner table, which is decorated. He goes outside and sprinkles petals on the sidewalk to the entrance. Then Darwin notices him sprinkling petals to create a path to the house]
Darwin: Oh, is Penny coming over?
Gumball: [Face stretched] No, Arran.
Gumball: [Face stretched] Arran.
Gumball: [Removing the hair clip to relax his face]Alan.
Darwin: Oohh, because you feel bad for constantly being angry at him for no valid reason, like when we did Secret Santa?
Gumball: Come on! It wasn't that bad.
[Flashback to the Secret Santa event held in Miss Simian's classroom; Gumball tears the wrapping off the gift he received to reveal a limited edition The Tale of Zelmore game]
Gumball: Gosh darn it, man!
Alan: You don't like it?
Gumball: I love it! It's thoughtful, expensive, and it makes my present look like something a rat would barf!
[Gumball violently throws his gift for Alan across the room and it breaks a window on the way out]
Gumball: [Embarrassed] It was a pair of fingerless gloves because you don't have fingers. But I just realized you don't have hands either, and yes, that makes me feel even worse!
[Flash to the present]
Gumball: Nah, it really wasn't that bad.
Darwin: Dude. When he apologized for making you feel bad, you roundhouse kicked him. And when he kindly said not to worry about it because his father is a surgeon so he wouldn't get a scar, you just–
[A momentary flashback to the Secret Santa event; Gumball is madly trying to attack Alan with a pencil while Darwin and two other classmates are struggling to hold him back]
Gumball: Fine. It was quite bad. But I'm not angry at him, I'm angry at myself... Ok, I'm also kinda angry at him for making me feel bad about myself. Either way, [Yelling] I'm gonna stuff this perfect meal into his perfect face! [calmly] You know, as an apology.
[The phone rings in the living room. Gumball picks up the receiver]
Gumball: Hello? ... Oh, ok, no problem. [Hangs up the phone and begins victory-dancing excitedly] Alan's not coming 'cos his mother is sick! I really shouldn't dance 'cause [Faltering] it sounded quite serious...
Darwin: [Sitting on the couch with a laptop] Maybe Alan's not coming because he's having too much fun somewhere else.
Gumball: [Sitting down next to Darwin] Nah, as I said, his mom's sick and Alan's not–
[Darwin passes the laptop to Gumball, who sees a picture of Alan's family in a car]
Gumball: [Reading the caption] Ready for an awesome day out...
[He hands back the laptop]
Gumball: Eah, that could've been taken weeks ago.
[Darwin points to the picture on the screen. In the background, a frustrated Gumball can be seen dressed like he is today as photographic evidence of the photo's recency]
Gumball: [Angry] Gaaargh...! Gaaaaargh!
Darwin: You don't even like the guy. Why do you care?
Gumball: Because he lied about his mom to get out of our dinner! He's a traitor!
["Ding!" Gumball and Darwin check the screen to see Alan's new status update: a picture of him and his family sitting at Joyful Burger]
Gumball: At Joyful Burger!? [He gasps as he gets an idea] Are you thinking what I'm thinking?
Darwin: That you're gonna catch him red-handed?
Gumball: I was thinkin' lunch, [Yelling] but that's a much better idea!
Catching Alan in the Act
[The scene changes to show Gumball and Darwin running into Joyful Burger. Larry is nearby wiping a table]
Gumball: Ah, we're too late – the suspects fled! But where to...?
Darwin: Excuse me Larry. Have you seen a round guy that's blue? He's this high [Shows a height with his hand], or sometimes this high, or this high– err– it kinda depends on the air temperature.
[Larry shrugs and moves onto another table; Gumball sees where Larry is heading and gasps as he gets an idea]
Gumball: [Yelling] Evidence! Get away from my crime scene! [Shoves Larry aside] Hmm... [Marking the "crime scene" with mayonnaise for chalk] You can tell from this splatter of ketchup that these fries were eaten in a hurry. [Pointing at a greenish glob by the fries] But what's this?
Darwin: [Gasping quietly] What?
Gumball: Enhance image.
Gumball: [Yelling] Enhance image!
[Darwin sighs and lifts the tray closer to Gumball's face; Gumball plucks a finger into the green glob and tastes it; Darwin puts down the tray impatiently]
Darwin: So, what is it?
Gumball: Let's just say it's not ranch dressing. Looks like the feelings of guilt got too much for Alan's weak stomach.
People in the background: Ewww!
Gumball: So he went for the light salad dressing instead!
People in the background: Oohh...
Gumball: [Angry] You seriously thought I would– wha– gross...! [To Darwin] Okay, so where did they go in such a hurry?
Darwin: Freeze! [He stares into Gumball's eyes] Enhance image. [Gumball takes a step closer] Zoom in on the eye. [Gumball takes another step closer, bending his knees a bit; Darwin gasps] Look! In the reflection!
Gumball: They're going into the movie theater!
Darwin: How did you guess!?
Gumball: Dude. I was looking at them.
[Gumball looks around, then grabs the glasses off the face of Melted Cheese Guy, who was sitting near by]
Gumball: Hah! Looks like this balloon...! Umm... Thi-this bubble...! This g'umm– this balloon's bubble is... going to... burst? [Darwin tries to speak up] No no– I'm nearly there– uh – s-s-something with hot air– uh– full of air!
Melted Cheese Guy: Looks like this balloon's cover is blown!
[Gumball sighs and holds out the glasses. Melted Cheese Guy puts them on with style]
Melted Cheese Guy: Yeeeaaaaaaaaaaaaaaaaah!!!
[Gumball and Darwin walk off. The scene changes to Gumball and Darwin outside a showroom at the movie theater with a large bag of items by them]
Gumball: ...and then he says "Please forgive me!" and then I say "I'm sorry! Forgiveness isn't on the menu but the chef recommends the sweet vengeance!" And that's when you throw the maple syrup. And then I say "Don't worry – the topping is much lighter!" And then you throw the feathers!
Darwin: Isn't that a little over the top?
Gumball: I didn't spend an hour plucking chickens for you to wuss out.
[Darwin sighs; they get into the room; Gumball pops up and down between rows as the sounds of an oddly fitting action sequence of the movie playing is heard. He appears last behind a balloon-shaped figure sitting at the front row]
Gumball: Get ready for justice you lying, bloated, empty-knotted, rubber sack of gas!
[Gumball dives onto the figure and picks it up]
Billy: Aah! Mother!!!
Gumball: Wait, what!?
Felicity: My chiiiiild!
Gumball: Darwin! Do something!
[Darwin, overexcited, yells as throws maple syrup, and then feathers, on Billy; the movie is stopped and the lights flick on; the whole room gasps at the sight they see on the front row, all glaring at Gumball and Darwin]
Gumball: [Nervous, still holding up Billy] Okay guys! When I explain everything you will realize that I am the true victim here, 'kay?
[The scene cuts to the theater security staff about toss Gumball and Darwin out the front door]
Gumball: Wait, wait! I'll do it myself!
[They are put down; Gumball steps over to Darwin, picks him up and tosses him out, before calmly walking out after him]
Gumball: [To the guards] Thanks.
Darwin: [Picking himself up and dusting himself off, fed-up] Maybe we should just give up.
Gumball: Are you kidding?! He's manipulated and tricked us, with no respect for our feelings! All this to settle the score with me, because he's jealous of someone else being so comfortable in their own skin!
Darwin: That doesn't sound like Alan. It sounds like you.
[Alan's family, in their car, pass right in front of them]
Gumball: [Furiously] THERE THEY ARE! [Normally] Quick, give me a quarter!
Gumball: If I can pierce their gas tank it'll leave a trail that'll lead right to them! All I have to do is throw the coin so it bounces off the lamppost then deflects off the ground up into the tank which - Oh, they just stopped at the park.
[The scene cuts to the two of them running into the park]
Darwin: Aww, noo - they already left!
[Gumball gets down and puts an ear on the ground. He picks up a pebble and licks it intently]
Darwin: So where did they go?
Gumball: Gee, I don't know - the guys float - they don't leave tracks.
Darwin: Then what was that all about?
Gumball: Eah, it's just a bit o' bread. [Tosses the "pebble" in his mouth]
Darwin: So they must've come here to feed the ducks!
Gumball: So all we have to do is interrogate the ducks to know where Alan went next! You can speak Animal!
[The scene cuts to Darwin by the pond, listening intently to some ducks quacking at him]
Gumball: [Whispering excitedly] So, what did they say?
[The scene cuts to Darwin and Gumball walking through the suburbs as they sulk in defeat; Alan's family's car passes by them again; Gumball let's out a battle cry and sprints after it; Gumball runs after Alan's car; cut to Tony walking toward Gumball, who runs through Tony causing him to explode, then Hot Dog Guy is seen walking the sausage dog and Gumball runs through him, causing both of them to explode; Pantsbully is eating a hot dog and, once again, Gumball runs through him and causes an explosion; Gumball then follows the Keane's car into the hospital parking lot and bumps into Julius; surprisingly, nothing happens]
Gumball: I-I-I dunno, I just expected you to–
[Julius explodes too]
[Alan and his parents enter the elevator, and the doors close just as Gumball gets to them]
Gumball: Noooooooo! We've lost them!!!
Darwin: Quick!! The stairs!
Gumball: Oh, yeah.
At the Hospital
[Cut to Alan's hospital room]
Gumball: [Entering the wrong room; off screen] You got busted! [Wrong room again; off screen] You got busted! [Bursting through this room's door this time] You bot gusted! [Whispering] Oh dagnabbit, I messed it up!
Gumball: Everyone thinks you're so perfect, so I invited you over to make up for the way I treated you, but to avoid hanging out with me you lied about your mother being ILL!!!!
Alan: But my mom is ill.
Gumball: Or maybe she's just exhausted from all the fun she's been having today! [To Jessica] Stop pretending! Hey!! [Pops a smiling balloon that looks like a "get well soon" gift, next to the hospital bed]
Alan: That was my Uncle Phil!
Darwin: Alan, what's really going on here?
Alan: [Sighing] The reason we're here is because my mom is having a flatulum transplant today.
Darwin: What's that?
Alan: The flatulum is an organ only balloons possess. We each have two. They regulate the airflow through our balloon knots. She couldn't find a compatible donor so I decided to give her one of mine.
[Gumball and Darwin breath in with guilt and embarrassment, biting their lips]
Alan: She's scared of the hospital. So my dad and I wanted to give her the best day possible before her operation. We took her to Joyful Burger, because that's where she met my dad!
[Gumball and Darwin breath in with guilt and embarrassment, biting their fists]
Alan: Then we took her to the cinema because she used to dream of being an actress before she decided to devote her life to charity.
[Gumball and Darwin double-facepalm in guilt and embarrassment]
Alan: Then we took her to the park because that's where she used to take me as a child. [Dreamily] Hmh, happier times. I'm sorry I bailed on our meal, Gumball, but she needed me.
[Alan notices dirt flying by his face. He sees Gumball and Darwin rapidly digging a hole amid the room]
Alan: What are you doing?
Gumball: We're digging a hole so we can wallow in our shame!
Alan: Before you do, can I ask for some help?
Gumball & :Darwin: [Desperately] Yes, anything!
Alan: You see, my dad's a surgeon and was due to perform the operation but you knocked him out when you burst through that door.
[Camera turns to a beaten balloon person squished between the glass of the door and the wall]
Alan: It would be really helpful if–
Gumball: Say no more, my friend! We'll perform the operation and we'll save your mother!
Alan: No! I meant you could just go down the corridor and find another surgeon that would–
[Darwin sticks the nozzle of the anesthetic gas on Alan's face. Alan struggles for a while]
Alan: Seriously! There's medically qualified professionals all over...
[Scene fades over to the operation room where pulse monitors show normal readings and Gumball and Darwin are dressed as surgeons]
Gumball: Okay... Flatulum transplant... Any ideas?
Darwin: Try this! Elmore Biology!
[Darwin gives gumball a picture book supposedly depicting the anatomies of different Elmore residents; however the book is a little weird, as Sarah and Hot Dog Guy appear to have skeletons and Rocky has a skeleton shaped like a giant hand referring to him being a puppet; they finally find the right pages]
Gumball: Ah, balloons! There! Flatulum transplant! Okay... [Visual instructions involve sticking one's hand through the balloon knot] Uuhh, ooh.. Not okay...
[Gumball peers through Alan's knot while Darwin examines the book]
Darwin: Look to your left. There should be a gland.
Gumball: Mmmm, no...?
Darwin: Okay, look to your right...
Gumball: Mm... nope!
Darwin: What can you see?
Gumball: Nothing! This guy is full of air.
Darwin: Let me look... [Stuffs his face through the knot; his voice is changed from inside Alan] Oh, you're right, all his organs are made of air!
Gumball: Just grab anything; it'll probably be the flatulum.
[Darwin pokes around inside Alan and pulls out an invisible airy organ, which suspiciously sounds like a beating heart]
Gumball: Uuuhhh, no.
[Darwin plugs the organ back in]
Darwin: It's all invisible! How are we supposed to do this opera–
[The peg that was holding Alan's undone knot pops off and air starts gushing out; Darwin screams]
Darwin: Ahh!! He's gushing air everywhere!!
[Gumball and Darwin are horrified as air blows all over their faces; Alan's heart rate monitor beeps without interruption as Darwin grabs hold of an invisible organ and passes it to Gumball]
Darwin: Here, grab the flatulum!
Gumball: Got it!
[Gumball fails to grasp the slippery air organ and drops it onto the floor and shouts out in horror of what he's done; he falls on his knees and fumbles to find it]
Darwin: Quick! We're losing him!
Gumball: Give him CPR!
[Darwin tries, but it makes even more air come out, in bursts]
Darwin: It's not working!!
Gumball: Then try something else!
[Darwin steps in front of Alan in determination, tears off his surgical mask, and begins to blow in air to re-inflate the balloon; at that moment a band-aid doctor throws open the operating room door]
Doctor: What's going on he–
[He sees Darwin, gasps and backs away. The door swings closed]
Darwin: Uh– I think the anesthetic's worn off!
Gumball: How can you tell?
Alan: MY INSIDES ARE POURING OUT!!!!
Darwin: What do we do!?
[Darwin and Alan are both screaming; Gumball, unamused, licks a finger and pokes it into the balloon opening, like a plug]
Gumball: ..Okay, now look for his flatulum.
[Darwin takes a step and slips on an invisible organ]
Darwin: AAH! ... Found it...
Gumball: [Determined] Then scrape it off your shoe and prepare for surgery!
[The scene cuts to Gumball's face as he is immensely concentrated on the operation he's doing. Darwin presses a towel on Gumball's forehead to remove the sweat]
Gumball: Scalpel... [Darwin hands it over] Forceps... [Darwin hands it over] Mayonnaise... [Darwin hands over a jar of mayo; a moment later Gumball picks up the sandwich he just made] There you go!
[Darwin bites it with delight]
Darwin: Mmm, that's really good!
Alan: [Waking up] Huh, whah? What are you doing!?
Gumball: Havin' lunch. The operation was a complete success!
[Gumball and Darwin high five]
Gumball: Dude, weren't you wearing a watch?
[Darwin looks at his wrist, confused]
Alan: Guys, please! How is my mom?
Gumball: [Warmly] Why don't you ask her yourself?
[Alan notices his parents on the next bed; they look tired, but well; Alan gasps]
Alan: [Gasps] Mom! [Turning back to Gumball] Thank you, Gumball, for saving my mother!
Jessica: [Speaking oddly, from her knot] Yes, thank you!
Alan: What the...!? Is she talking out of her backside now?
[Gumball stands up in anger and smashes the mayonnaise jar on the floor]
Gumball: [Reprimanding] Oh, nothing is ever good enough for you, is it, MISTER PERFECT?! Since when did you have a surgeon's licence!? Oh, but please! Judge away! Looking down from your high horse, making everyone feel like-