Mr. Peanutbutter's posh campaign fundraiser takes a terrifying turn. As chaos swirls around them, BoJack and Diane get drunk.
BoJack goes over to her house and learns that they are having a fundraiser for Mr. Peanutbutter's campaign.
The security guy won't let him in unless he pays. Mr. Peanutbutter comes over and talks to Bojack but doesn't get him in. BoJack begrudgingly pays $20,000 for a plate.
Princess Carolyn asks Diane if there are any other bathrooms because all of them are occupied. She has to pee, but makes it clear that it's not because she's pregnant, because if she was pregnant it would be bad luck to announce it that early. Diane tells her that there is a bathroom in the pool house.
Mr. Peanutbutter tells Diane that she looks gorgeous and they kiss, but BoJack walks in and ruins the moment. Mr. Peanutbutter excuses himself to go talk to two of his ex-wives, Jessica Biel, who likes getting photographed at fancy events, and Katrina, Mr. Peanutbutter’s campaign manager. Diane tells BoJack that she's busy and can't talk to him as an excuse to avoid him. Famous actor Zach Braff walks around the party greeting everyone.
Mr. Peanutbutter begins to makes a toast promising to beat Woodchuck Coodchuck-Berkowitz and thanking his pro-fracking supporters, when he suddenly senses an earthquake coming. Nothing happens, and Mr. Peanutbutter assumes it was a false alarm. An earthquake immediately occurs, putting all the guests in panic. Some guests begin confessing their regrets, leaving to Diane shout "I regret everything!". The earthquake stops, but the entire house falls into a large sink hole.
Everyone wakes up to find that the house has remained intact, but they are trapped underground. Mr. Peanutbutter tries to calm everyone down, but fails. He goes to comfort Duane, but she angrily tells him that this is his fault because of his fracking, despite her telling him not to, and she storms off.
She goes into the bedroom and finds BoJack hoarded up in there with all the alcohol. He says she can either be mad at him or get drunk with him, but not both. She says "Watch me" as she begins to chug down a bottle of alcohol.
Princess Carolyn walks out of the pool house and learns of what just happened.Hse finds Todd in the poolhouse’s bathtub. He explains he was going to go to the party after his bath, but then he realized the bath was the party. Princess Carolyn says that she isn't going to wait around to be rescued, so the two of them head down a dark tunnel.
Mr. Peanutbutter again tries to calm everyone down. He tells them that they are important celebrities, so someone will come to rescue them soon. For now, they decide to put on a show where everyone is the star. Mr. Peanutbutter promises they’ll be out in no time, and the guest cheer.
Phoebe, one of the party guests, finishes her monologue and Mr. Peanutbutter asks who's next. Jessica Biel complains that she can’t take it anymore and needs to get out, which prompts others to complain as well, saying it’s been 72 hours. Mr. Peanutbutter again tells them to calm down. Katrina tells him that he can do this, and that he needs to be the leader she knows he can be. Suddenly, Woodchuck bursts through the wall.
Diane and BoJack, both extremely drunk, come out, and Mr. Peanutbutter asks if she's just been drinking the whole time. They both laugh drunkenly at him.
Woodchuck announces that rescue workers are coming, but it might be a while, due to state emergency funds being depleted due to the building of a bridge to Hawaii. Woodchuck explains that because he can dig he's come to rescue them. Mr. Peanutbutter asks if the rest of the neighborhood is in shambles, but Woodchuck says that it's just his house because of all the fracking under his house.
Mr. Peanutbutter encourages the guests to cheer for Woodchuck, but Woodchuck tells them the tunnel is extremely delicate. They all ignore him and cheer anyways, causing the tunnel Woodchuck dug to collapse. Woodchuck tries to escape before that happens, but gets his hands are crushed underneath the rubble.
Princess Carolyn and Todd continue walking down the tunnel. Todd hears something scuttering, but Princess Carolyn tells him to just keep walking. Todd complains that he doesn't have a home anymore, but Princess Carolyn tells him that he can crash at her place, saying that even though she moved in with Ralph she still kept her old apartment "just in case".
Suddenly, they are surrounded by ants, all of whom are dressed in armor. When Todd says Princess Carolyn's name, they pause and ask if she's a princess. She says it's just her name, and that she's a manager. The lead warrior ant says that she can be of service and takes them away.
Meanwhile, Woodchuck's hands are severely broken, and he can’t dig them out. Mr. Peanutbutter says he could try, but Pinky says the foundation is so delicate now one provocation would cause another collapse that would crush and kill all of them. As Jessica Biel tapes pillows onto his broken hands, Woodchuck says until someone comes for them, they have to organize.
The party guests are much more relaxed now, having organized themselves. Mr. Peanutbutter is in charge of the food rations, having reliquished control to Woodchuck, much to Katrina's dismay.
BoJack steals more rations than he's been allocated, which angers Woodchuck so he confronts him. Mr. Peanutbutter decides to intervene to prove he’s a leader, and the others begin to question why Woodchuck is in charge.
BoJack makes a hasty exit and goes back to the room with Diane. Diane is laying on the floor, complaining about how she's going to die trapped underground because of her husband, and surrounded by his ex-wives. Bojack tries to assure her that she has a good life, but this makes Diane realize that she wasn’t happy above ground either. She breaks down crying, saying she’s the problem and she can’t be happy. She calls herself a pit good things fall into. She felled bad for crying, but BoJack assures her it’s fine, and to not feel bad about feeling bad.
Diane asks BoJack why he didn't call her when he came back to LA after being gone for a year and a half. BoJack says that he wasnt ready, and wanted to be better when she saw him, although he doesn’t think that could ever happen . Diane says that he doesn't have to be better, and that he's the only thing that makes sense to her as she cuddles up next to him.
Outside, Mr. Peanutbutter and Woodchuck argue over leadership. The guests begin to turn against Woodchuck for failing to save them, and Mr. Peanutbutter declares himself the new leader as the guests chant his name.
After they wake up, Diane asks BoJack if he's okay. He says the last few years have been rough, and he tells her about his daughter, Hollyhock, and how he’s trying to help her find her mom. Diane tells him he has to contact the adoption agency and send a mutual consent form to make her afolption open, and if her birth mom says the same thing, she can meet her. BoJack questions why she knows this, and Diane says one of her brothers was adopted, and for a while she wished she was adopted.
The ants take Princess Carolyn to Queen Antonia where Princess Carolyn presents their case - the ants feel like they're doing all the work while the Queen does nothing. Queen Antonia asks what their demands, are and they say that they want to have sex with her drones. Queen Antonia calls a meeting of the small council.
The party guests continue to rally against Woodchuck. As Jessica Biel declares Mr. Peanutbutter President for life of the Underground, the guests and Mr. Peanutbutter decade to tie Woodchuck so that he doesn't get in the way. Mr. Peanutbutter also declares that everyone can eat and drink whatever they want.
As a result, everyone is starving because they ate all of the rations. During this, Woodchuck has been tied to the ceiling fan. Jessica Biel says no one is coming for them, and that they need to kill someone for food. They decide to eat Mr. Peanutbutter, because of his name, but Zach Braff intervenes and begins to give a heartfelt speech about not giving up.
However, Jessica Biel sets him on fire, and declares that fire is law. Everyone, including Katrina, side with the fire. Jessica announces tonight they're going to dine on Zach Braff, and that tomorrow they'll eat Mr. Peanutbutte, and she has him taken prisoner.
BoJack tells Diane the secret to being happy is to pretend to be happy, and eventually you'll forget that you're pretending. Diane decides that’s not bad advice. Mr. Peanutbutter is thrown into their room, and explains that fire is the new ruler, and he’ll be fed to it the next day. BoJack and Diane are forced out of the bedroom.
Princess Carolyn sits at a table surrounded by Ants and their Queen. The Ants are satisfied by the agreement that they've come to. Queen Antonia asks Todd how they came to be underground, and he tells them about the earthquake in Beverly Hills. Queen Antonia and the Ants voice their disdain for "above grounders", and 5he queen orders her servants to take the two of them away.
Mr. Peanutbutter has been tied to a makeshift cross and is about to be burned by Jessica. BoJack and Diane, still a bit drunk, try to figure out what to do, and realize that there might be a well of water beneath them. They start digging despite Woodchuck's protests for them not to.
Right when Jessica Biel is about to burn Mr. Peanutbutter, BoJack hits a pipe and water is released into the room. Everyone rejoices, until they realize that the water isn't stopping.
The water has almost filled the entire house, with the guests floating just beneath the ceiling. They are about to drown the house when begins to move. Outside, the Ants have joined together to bring the house to the surface, as they want them out of there, although it crumbles to pieces immediately afterwards. Jessica Biel tells them that they are never talking about this again as they all walk away.
Christina tells Mr. Peanutbutter the agenda for his campaign the next day before she leaves. Diane tells Mr. Peanutbutter that he's the best thing that's ever happened to her, and that if he really wants to be governor then she'll support him. Mr. Peanutbutter says he doesn't want to be governor, because he’s a terrible leader and he just wanted people to like him. The two of them begin to leave, but realize they already are home.
Princess Carolyn and Todd join them, and the former congratulates them on a great party. BoJack joins the group. BoJack breaks the tension and suggest getting Ethiopian food, which leads to a conversation about how they have good bread.