Finn and Jake are climbing a mountain to find a cave that is shown on a map from Flambo's brother close to where the dungeon train is. When they find it, Finn goes inside, accidentally stepping on a pressure plate and trapping himself in. He finds three passages and decides to go through the middle one using a thread from his shirt to leave a trail. Finn walks without looking and falls down a steep slope, arriving in a medium sized room with sunlight shining through and a mixed-up snowman statue in the middle. They are followed by a huge door like the ones in a submarine, with the words "Hall of Egress" printed on a banner above the hatch.
Finn tries to open the hatch and fails multiple times. Finally, in exhaustion, he rests his head against the hatch. His head falls through the hatch and on to the ground. He opens his eyes and finds himself back in the hall. He then closes his eyes and reaches out. His hand passes straight through the hatch. He walks forward, past the door. He opens his eyes and finds himself back in the hall. He tries again and finds a string. He follows the string until he falls down a hole. Hanging on the edge of the hole he slowly lets his foot down. He discovers that he fell into a spike trap. He opens his eyes and finds himself back in the hall.
After many failed attempts at finding a way out, Finn just charges through the door. He keeps running until he hears Jake's voice calling him. Finn continues running and eventually pops out of the ground by Jake's feet. He opens his eyes and he is back in the hall. He then repeats himself, only not opening his eyes when he unearths. He returns to the Tree Fort with Jake and goes to sleep, hoping it will be better in the morning. In the morning Finn is pestered by BMO to open his eyes. He does and instantly finds himself back in the hall.
Finn repeats the same thing over and over, each time either BMO or Jake forces open his eyes. Each time he finds himself at the hall. Finn eventually leaves one night from the Tree Fort, while Jake and BMO are asleep. He wanders off into the night and eventually reaches a stream. Here he takes a drink and strips himself of his clothes. He dons an animal skin and wanders through many kingdoms over many days, progressively getting dirtier. He eventually reaches a cave, like the mountain cave but in a desert.
Finn walks into the cave, his dirty feet narrowly avoiding a pressure plate. He reaches another three passages and once again chooses the middle path. He walks down the steep slope, now with a ramp. He reaches the hall and walks until he arrives, unknowingly, at the hatch. He bumps into it, finding that he can not pass through it. BMO's voice rings out through his head, stating the words "Something is different". Finn opens his eyes to see a see-through passage ahead of him where the hatch used to be. He walks in, seeing animals walking above him on the seemingly clear ground. In the distance he sees Jake looking for him.
Finn breaks in to a run. In his head, Princess Bubblegum's voice says "Hurry Finn. At the seashell's centre lies the Cornucopia's smallest door". Finn runs faster and breaks out of the ground, spraying rubble all over Jake. Finn leaps on to Jake and warmly embraces him. He spins Jake around. Jakes laughs and says "That must have been some cave". Finn replies "No comment".
- The Dungeon Train is seen again for the first time since its debut in the titular episode.
- The Hall of Egress may be the weird cave mentioned in the episode Dungeon Train.
- Also, near the end of Dungeon Train, Finn shows Jake the future in an orb, which shows a scene of them washing the dishes with Finn having his eyes closed, from this episode.
- This was the first episode of Adventure Time to debut on a Saturday.
- There is a deleted scene in which Flambo's brother makes a physical appearance. It was likely cut for time.
- Finn laughs off Jake mentioning his breakup with Flame Princess, suggesting he has finally gotten over her, although he does mention it sucked.
- Finn refers to himself as "Finn Mertens" again, suggesting he now accepts it as his surname.
- ↑ http://tvschedule.zap2it.com/tv/adventure-time-hall-of-egress/EP012462650993?aid=tvschedule
- ↑ https://landofooo.com/community/attachments/11219579_408333809372098_7758364907426163461_n-jpg.245/
- ↑ http://www.toonzone.net/clip-cartoon-network-premieres-for-february-29-2016-clarence-we-bare-bears-regular-show-more/