The episode begins with Buckey O'Neill on the TV, sitting by the fireplace, telling a story about how he discovered chicken nuggets and "founded" the town of Aberdale. Sumo is mesmerized by the TV while he watches the same video constantly repeat over and over again. Clarence is dancing and singing about how much he loves the food and Jeff tells him that he only likes the fries. Clarence keeps asking him if he likes any of the other food there but he keeps telling him that he only likes the fries. Clarence initially is shaken up, but then asks "What about the Fun Dungeon?", as he gestures over to a playpen with a bunch of little kids running around in it. Jeff cringes in fear. Mary goes up to the counter and orders some food. Clarence orders a Hip Watchers Salad and when Sumo orders, he speaks so fast and slurry, that the cashier can't understand him. Clarence translates the stuff that she says to her. When Jeff orders, he orders a scout meal without the burger. The cashier tells him that he can't order a scout meal without a burger. Mary suggests that he just order it with the burger and give it to Sumo instead. Jeff continues to argue that he wants to have a scout meal without the burger. Mary whispers to the cashier to just put it on the side.
They all go to their table where Jeff takes a girly cow toy out of his bag. He sighs because that's not what he wanted. He takes out his burger and Sumo tackles it and goes to the the ketchup machine, smothering the burger in ketchup. Clarence asks Jeff if he likes the Fun Dungeon but Jeff tells him that he doesn't like it because it's gross because kids probably throw up in there and nobody cleans it. Clarence and Sumo start eating their food in a very sloppy and messy way. Jeff is scared by this and then he excuses himself to go to the bathroom. Clarence then asks if he can have one of his fries and Jeff angrily declines. He then asks Clarence to promise him to make sure that he nor anybody else touches his fries. Clarence promises him that he will do that. Jeff slowly walks away to the bathroom, looking back at Clarence. As soon as Jeff goes out of sight, Clarence grabs Jeff's box of fries. He tells Sumo that this is a plan to get him to come into the Fun Dungeon with him. He puts the fries into his back pocket and they both run into the Fun Dungeon.
When Clarence and Sumo get into the Fun Dungeon, Clarence puts his shoes in the cubby and takes out another pair of light up girly shoes from another cubby and puts them on. When they hear Jeff coming, they both run and hide behind the slide. When Jeff sees that his fries are missing and one of them is lying in the seat where Clarence was, he freaks out and chases them into the Fun Dungeon. Clarence climbs into the ball pit and swims through there while Jeff angrily chases after him. Clarence climbs up into the net tunnel and them Jeff grabs the end of it and whips it, making Clarence slip and fall, getting his arms stuck in the holes. Clarence quickly pulls them out of there and crawls away before Jeff can get to him. Clarence goes to some tunnels and tries to decide whether he should go into the pink or blue one. He chooses pink and Jeff chases after him. In there, he sees a little girl who says "Hi" to him. Jeff goes to a window and looks for Clarence. He sees Sumo in the restaurant playing with the girly cow toy. Suddenly, a giant hand covered in grease and ketchup slams onto he window which scares Jeff. The hand is revealed to be Clarence who is on top of the tunnel. Jeff sees a broken window of which Clarence must have went through to get on top of there and he punches it out and gets on top of it. There, he rips the foam padding off of the metal bars and starts slapping Clarence with it. Clarence gets another foam patting and uses it to defend himself. They jump down into a lower tunnel and Jeff keeps swinging and hitting the foam patting at Clarence while Clarence backs away, defending himself. This draws attention from all of the other kids in the Fun Dungeon.
Mary is back at the table and her friend Sammy comes up and asks if her son Sean can play with Clarence. Mary says that it would be great if he could do that because everyone loves Clarence. The scene then shows Jeff screaming that he's going to kill Clarence. Clarence goes inside of the playpen and goes to the slide where he slips and falls in but he catches himself with his feet and hands. Jeff puts his foot on Clarence's face and gives him his final warning to tell him where his fries are. Clarence reaches into his back pocket and pulls out the fries. He tosses them back at Jeff but by accident, he spills them out onto the slide and they go down. Clarence fears that Jeff will get mad but instead he just tells him that he has his own personal reasons and opinions for things that he would never understand. Clarence starts to slip but then Jeff grabs him by the leg and saves him. They both fall down the slide together where all the fries are at the bottom where Sumo is eating them. Mary comes up and tells them that they're playing too rough and it's time for them to go home.
They all go into the Parking Lot and Clarence apologizes to Jeff for what he did. Jeff tells him that he's sorry too for trying to kill him. Clarence holds out his hand which is covered in sauce and grease and salt and Jeff hesitantly shakes his hand. When he grabs his hand, Clarence clenches it with both of his hands and shakes it. They all go into the car, Clarence completely unaware he hasn't got his own shoes. Clarence asks Sumo where his girly cow toy is. Sumo lies to him, telling him that he doesn't care about "some girl toy", but in reality has a flashback to all the good times he had with that girl toy and how much he misses it, set to a song he sings.
The transcript for Fun Dungeon Face Off can be found here.