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The video presents itself as an instructional video for students at the beginning of a school year in Palm Valley High School, teaching them how to stay safe in the science classroom. Everything seems fine, if slightly off (why explain what cabinets are?) until the explanation for the exit door states "The exit is used to leave the classroom. You cannot leave."
The music briefly cuts out, and the video returns to seeming normal. The "Do's and Don't's" section is normal until the end of the Don't's, where one of the Don't's is "If you are to see a red substance in one of the beakers, do not resist the urge." The audio cuts to static and a message on a black bar is displayed, saying "THE CONTENTS OF THIS TAPE ARE RESTRICTED TO ONLY HIGH-LEVEL PERSONELL. ANYONE WATCHING THIS TAPE WITHOUT SUFFICIENT CLEARANCE MUST DISCARD THIS FROM THE PLAYER IMMEDIATELY." The video cuts out, and then goes back to normal for the Restrictions section of the tape.
This part speaks about how you must only do what your instructor (who, by the way, is never referred to as a "teacher" in the entire tape) tells you to do. The third "restriction" simply says "Blood flows within the walls." The video cuts to static again before the "Consequences" portion, which simply shows a diagram of several people surrounding a corpse and a tentacled creature, saying "Rulebreakers will be fed to them ."
The last part of the tape shows the camera from the classroom tour, now with flickering lights and the lens covered with strange black veins, before more tentacles surround it from the top and bottom. The video cuts out. Outro.