The older sisters reluctantly let Lynn into their babysitting club, but she quickly proves to be too aggressive.
Lori, Leni, Luna, and Luan are getting themselves ready for their babysitting duties. However, a fifth family needs their kids to be looked over, and the sisters are hesitant to appoint Lynn to the job, given how aggressive she can be towards others. In the backyard, Lynn, while swinging on the tire swing, startles Lana and Lola while riding in the Princess Car, and nearly hits Lily but Charles saves her at the last moment. The older sisters attempt to appoint Lincoln, but Lynn, saying that she's in the line of birth order, demands that she be given the job, and the older sisters begrudgingly accept.
Lynn is dropped off at the McCauley's, where she has to look after the two kids, Caleb and Camille. While Caleb and Camille have plans of their own, Lynn suggests that they do what she wants to do. Lynn has them wrestle, lift things that are too heavy for them (such as pickle jars and a whole uncooked turkey), and drink raw eggs. When the two want to go to bed, Lynn tells them a story of when she broke her tibia (the bone that connects the knee to the ankle bones), making them nauseous. Sometime later, Lynn arrives back home with a stack of cash, saying that she did a good job babysitting the McCauley kids. Just when the older sisters begin to think of Lynn differently, they receive a phone call from the McCauleys, revealing that Lynn had mentally scarred their kids, and as a result, they fired all of the other sisters from being their babysitters. Realizing that Lynn could ruin their reputation of being good babysitters, they tell Lynn that she's no longer in their babysitting club, but Lynn does not take this statement well.
The next day, the sisters' different clients call, and Lynn, wanting to prove that she can be a good babysitter, lies to them by saying that the other sisters are busy, and offers to babysit for them. When the older sisters question why they didn't get called in today, they decide to call their clients, when suddenly, they're told that they fired them from being their babysitters, because of what Lynn did to their kids. Needing a way to get back at Lynn for ruining them, they realize that they should make her babysit the Fox quintuplets, who are the sisters' worst customers, because of how wild and rambunctious they are. The sisters tell Lynn that they already booked her for another job.
After arriving at the Fox residence, Lynn soon discovers how much the quints like to misbehave. At the Loud House, the older sisters are initially happy that Lynn is getting some sort of punishment, but begin to feel bad out of fear that Lynn is going through the same trouble they went through, and decide to check up on her. Arriving at the Fox residence, they discover that the Fox quints are behaving. Lynn explains that because of her aggressive behavior, she was able to get the quints to listen to her. When the older sisters accidentally reveal that they secretly wanted Lynn to quit being a babysitter, they apologize, saying that Lynn does make a good babysitter, and just needed a family that has the same amount of recklessness are her. Lynn apologizes as well for driving the other clients away. The older sisters decide to head back home, and the quints are ready for bed.
The next day, Lynn is off to babysit the quints again, and tells her older sisters that because she did such a good job, Mr. and Mrs. Fox have appointed her to be their daily babysitter, and reveals that after a lot of begging, she managed to convince the clients who'd fired the older sisters earlier to rehire them, for which the older sisters are grateful. At the Fox residence, Lynn has a fun time wrestling with the quints, where they declare her "best babysitter ever!"