Ben, Gwen, and Max meet a family that appears to be a mirror image of them, but when Max goes off on a hike with their matriarch, Maxine, Ben is forced to babysit Simon Sez, a brat with a Billy Billions designed backpack that turns him into a formidable robot.
The Tennyson's ride through a hot desert. Ben gets excited about visiting the ranch. Ben transforms into Stinkfly and stars shooting things with his goo. Ben starts annoying Gwen. The team arrives at their destination. Ben runs out ready to have fun, but immediately Ben and Gwen run back inside the Rustbucket because of the heat. Max laughs at them, but soon he realizes how hot it is. He then looks over to someone calling him.
Back inside the Rustbucket, Ben and Gwen try to cool off using the air vent. Max enters the R.V. telling them that he found a camper that looks just like the Rustbucket, and the lady told him about a hike. He tells them that they get to stay in the Rustbucket. Max introduces them to Maxine. He tells them that she is also on a road trip, just like them. Her grandkids didn't want to go either, so Maxine introduces Ryan and Simon. Gwen immediately develops a crush on Ryan. Gwen rushes Max and Maxine out of the R.V. Gwen asks Ryan questions, and Simon asks Gwen questions too. Simon tells Ben that he has a backpack that turns him into a robot. Ben gets annoyed by Simon's talking. Ben runs over to Gwen to ask if they can switch spots. Gwen gives him money and tells them to go get ice cream.
Outside, Ben thinks about turning into Overflow to turn down. Right before he hits his watch, Simon stars asking questions again, and Ben stops and walks away. As they walk, Simon asks Ben even more questions, which annoy Ben even more. Ben yells at Simon, and that makes Simon angry. Ben apologizes and offers to carry his bag. However, Simon gets mad and pushes him off. Simon runs off, and Ben notices his backpack is from Billy Billions Corp. Ben remembers Simon saying he has a backpack that turns him into a robot.
At the ice cream stand, Simon demands juice from the worker, but she tells him that they don't sell juice. Simon gets mad and pushes the button on his backpack, giving him a big robot suit. Right before he crushes the lady, Ben runs in and transforms into XLR8 and saves her. Simon goes through the town terrorizing things. Ben runs up to Simon and tries to reason with him. Simon however throws him off, ignoring him. XLR8 tries to detract him, since he can't hit him. He runs around him, calling him a baby. However Simon stomps his foot, sending XLR8 flying. Ben then times out. Up on a mountain, Max and Maxine are both hiking, talking about how much of a handful their grandchildren can be. Back in the Rustbucket, Gwen still tries to make talk with Ryan. At the town, Four Arms confronts Simon, tries to reason with him. Simon tells him that he wont listen to Ben since he didn't listen to him. Ben tells him that he was being annoying, and Simon gets mad and throws Four Arms around. Back at the mountain with Maxine and Max, Maxine sees an explosion and gets worried. Ben tries to be nice to Simon, but Simon just throws him around. Simon tells Ben that people always want him to listen to them, and they never listen to him. Four Arms tells him that he knows that feeling. He tells him that they tell him those things because they love him. He politely asks Simon to stop smashing things, but Simon insist on smashing him instead. Gwen and Ryan hears a big explosion. Ryan walks out telling Gwen that he has to go take care of something. Ben has enough and jumps up to punch Simon. However he times out. He lands in Simon's hand and right before Simon tries to hurt him, Ryan gives him juice, and everything is alright. Max and Maxine arrive, and both believes that their grandsons are responsible for the damage to the town. Both of them arrive at the Rustbucket to make sure everything's okay. Ryan and Ben are seen playing video games, and Ryan tells Maxine that Simon is sleeping. Right when the Sez family leaves, Simon thanks Ben for playing with him. Gwen asks Ben about the robot backpack. Ben tells her he took the batteries out, and it'll be years before Simon can save up for a new one. Ben tells her that Simon isn't that bad of a kid, and he could make a great ally someday. On the ground, Max is begging for water, due to the extreme heat.
Simon: It's hot. Are we there yet? I want to go home. I'm sweaty! My feet hurt. My backpack's heavy. When are we gonna get there? I want juice. Ben: (Groans) Got it! It's hot, your backpack's heavy, you want juice! Jeez, don't you ever stop? Simon: You hollered at me. (Sniffles). Ben: i didn't holler. Ugh. Look, Simon, it's -- it's hot. I just -- Here. Let me carry your backpack for you. Simon: No! You hollerer! I ordered this special. You think you can just touch people's stuff. Well, you can't I want my juice! Ben: Hey, wait! Billy Billions Corp.?
XLR8: I can't hit Simon since he's like 6. That's practically a baby. Time to go into full distract mode. Hey, Simon. Bet you can't hit me. Simon: Can too. XLR8: (Laughs) Falling for easy jokes like this? Baby.