Following the previous episode, Stan almost opened the portal and decides that no one's going to stop him, and everything's going to change...tomorrow.
Next morning, the twins and Grunkle Stan playing with fireworks. Stan is about to talk with the twins, saying that there's something he wants to tell them about, but he walks away, nervous to tell them about his secret.
Moments later, FBI agents, Powers and Trigger arrive and arrest Stan, much to the twins' shock! They are shocked of seeing Trigger and Powers, after believing them to be dead as a victim of zombies in the Scary-Oke episode, which the men explain that they have survived and arrest Stan for stealing the radioactive waste. The twins protest it, until they Powers tell the twins that under the shack is apocalyptic machine. Trigger takes care of the kids, while the agents take Stan into custody. Before being taken away, Stan tries to yell out at the kids that he is innocent.
In the custody, Stan tries to deny his guiltiness, but then he goes to take a little phone call. Stan calls Soos, who's on a panic food for hearing Stan arrested, until his boss tells him to protect the vending machine in the gift shop (which is actually a secret hideout). Believing it's a serious mission, Soos grabs his lunch, before bravely and heroically heading off to the Mystery Shack.
Meanwhile, Dipper and Mabel are confused with their uncle being a criminal. They made Trigger's gip crash after making themselves being ran over by Manly Dan (after Mabel manages to anger him by saying that Sev'ral Timez is overrated). The twins escape, leaving Trigger trapped in the van. The twins leave to save Stan's real name. Trigger explains that Stan is the one bad guy, Dipper listens to this, he hesitantly disbelieves it, and leaves with his sister.
Back in the custody, Stan realizes that it's only 5 o'clock, saying he has to be there. Gravity begins, lifting everyone high in air. In the junk yard, Old Man McGucket frantically packing his stuff and raccoon, saying that the end times coming with the portal activated as the old man leaves the junk yard.
Meanwhile, the twins return to the shack. After the twins found out that in the VCR cassette is Soos dances like a worm and Stan works, twins relieved that he is innocent. Soon their relief quickly turns into concern after Stan gone for a whole night. To make matters worse, much to their shock and horror, they realize that he took the radioactive waste and found the fake ID's, they wonder why would Stan do this, until they find a newspaper says:"STAN PINES DEAD", they are horrified to learn that their Grunkle Stan...isn't...Stan?!
The twins wonder how much they know about their grunkle, Dipper laments of how they've been blindly believed in their Grunkle. Mabel tries to deny this, saying that there's another explanation, until she found the code to a hideout, which Mabel realizes that it's the vending machine.
Back in the custody, Powers decides to arrest Stan, suddenly another gravity arrives as Stan uses it as a distraction and escapes. He tells taxi driver to drive away to the mystery shack as fast as he can as the cops drive to hunt him. Taxi driver shrugs and does so. Stan leaves back to the mystery shack as FBI agent start their hunt on Stan.
Meanwhile, Trigger arrives and informs them about Stan's escape and he is at large. The agents leave the mystery shack to start their hunt on the fugitive Stan. Once the agents depart, twins catch up with Soos, they ask him to turn around so they could use the vending machine, but Soos refuses, saying that he promised Stan to protect it. The twins, having no choice, but to fight their friend for vending machine. After a brief struggle, Dipper uses a code, it opens the vending machine, revealing the basement and they have entered the basement. They can't believe their eyes what they see with a confused Soos why is this all need to Stan. They also found three journals as enraged Dipper asks why does Stan have to do it. They read the from ultraviolet flashlight, they realize that if the countdown ends to the zero, their universe is doomed. Suddenly, the final countdown begins, Soos panics as Dipper realizes that FBI agents were right and they have to shut down the machine. They enter the portal room, where portal unleashes it's rage around as the lightning strikes. They found the button. Dipper decides that this all stops now as he was about to push the button.
Right before he pushes the button before the countdown ends, Stan quickly arrives at the scene and frantically begs him not to push the button. Infuriated, Dipper angrily berates Stan for stealing the radioactive waste and for lying to them all summer. Stan tries to explain, but suddenly another gravity begins, it lifts people, FBI agents, cars and objects. In the Mystery Shack, as everyone's flying to the flying rapids. Mabel is closer to the button as she flies off to push the button, Stan tries to stop the girl, only to be apprehended by Soos. Stan furiously asks Soos what is he doing, since he gave him an order to protect the vending machine, with Soos explaining that he has a new mission: protect the twins. Dipper joins Soos as both apprehend Stan. With Stan apprehended, Dipper tells his sister to shut the machine down, but Stan tells her she has to trust him. Torn between Stan and her brother, drives Mabel off to the edge. Mabel tearfully tells him that she wants to trust him, but she doesn't know what to believe, suddenly the portal's wave energy pushes three men to the wall. After a brief talk, Mabel decides to made a choice. Despite her brother's objections, she trusts Stan and lets herself to float, much to Dipper's dismay and outrage.
However it was too late. The countdown ends as the portal activates, ending up destroying everything, the explosion engulfs the Mystery Shack, but instead, it happened for a few seconds, gravity ends as the twins, Soos and Stan fall. By the time as the twins, Soos and Stan recover, all of a sudden through a portal, the hooded man enters and he has six fingers. Dipper surprisingly asks who was he, with Stan saying it's the author of the journals. The man uncovers his hood, as all learned that the author was Stan's long lost brother, as all watch in awe and shock. Mabel asks somebody has to faint, with Soos doing so as the end credits shows two brothers, swinging as the episode goes to another to show a tale.
- Kristen Schaal - Mabel
- Jason Ritter - Dipper
- Alex Hirsch - Stan Pines, Soos, Old Man McGucket
- Brad Abrell - Agent Trigger
- Jennifer Coolidge - Lazy Susan
- Nick Offerman - Agent Powers
- John DiMaggio - Manly Dan
- Linda Cardellini - Wendy
- Will Forte - Tyler Cutebiker
- Kevin Michael Richardson - Sheriff Blubs
- Matt Chapman - Additional Voices
- Kari Wahlgren - Additional Voices
- Written by:
- Shion Takeuchi
- Josh Weinstein
- Jeff Rowe
- Matt Chapman
- Alex Hirsch
- Directed by:
- Stephen Sandoval
- Storyboarded by:
- Sabrina Cotugno
- Alonso Ramirez Ramos
- Dana Terrace
- Luke Weber
- Additional Written Material by:
- Zach Paez
- Casting by:
- Sara Jane Sherman