"Underground laboratory" is Stan Pines's secret passage space inside the Mystery Shack hidden behind a vending machine. Stan secretly entering the room behind the vending machine is shown briefly in the episodes Tourist Trapped and in Dreamscaperers. But the whole inside of the room is finally presented in the Season 1 finale Gideon Rises.
In the very end of the first episode of the series "Tourist Trapped" Stan is shown mysteriously entering a room behind a vending machine which marked the end of the episode. The room wasn't mentioned in the following episodes until "Dreamscaperers" when Soos opens a "memory door" in Stan's mindscape where he finds Stan entering behind the vending machine saying "If only people knew the truth, that hidden behind this vending machine I secretly have a...". Soos gets bored and closes the door without listening to what Stan was going to say. The inside of the room is finally showed in "Gideon Rises" where Stan has collected all of the journals (1, 2, and 3) and with writing codes from them starts a device where the episode ends not showing what is Stan's intention.
In order to get inside the room Stan has to unlock the vending machine code, go through the series of stairs behind it, get inside an elevator and move three floors under the ground. The laboratory room is filled with retro futuristic looking computers, gadgets, and machines, all of them constantly working. On the end of the room is a desk with many electronic devices and on the side it has the symbol from Stan's tattoo. On the desk there is a picture from Dipper and Mabel, and in the shelf bellow a series of books in which Stan hides the journal number 1. Near the desk there is a door entering into a room consisting a triangle shaped device with a circle inside that has 16 symbols.
Only Stan entering
The whole room
- 120. Gideon Rises
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