|“||ARE YOU PREPARED TO GIVE YOUR LIFE TO SAVE YOUR SON'S?||”|
—The final trial
If Ethan has not been imprisoned, he makes his way down a red hallway into an elegant white room filled with mirrors and cameras and a vial, a stopwatch, and a media player on a table. The media player informs Ethan that the poison in the vial will kill him in one hour, but he will get the last letters of the address if he drinks it. After deciding whether or not to drink the poison, he will either drive to the address at which Shaun is being held or have to guess at the address based on the information he's collected.
- Main article: /Walkthrough
- Completion of all 5 trials: Ethan will find Shaun.
- Completion of 3-4 trials: Ethan must guess Shaun's location from available information.
- Completion of fewer than 3 trials: Ethan will fail to find Shaun's location, though if Madison survives "Killer's Place" and found the address in the computer she can give it to Ethan.
With the history of rats as carriers of disease the poison may refer to their role as disease vectors. The room is also synonymous with this, the corridor representing blood and the main room representing cleanliness. Alternately, the fact that rats have been poisoned for centuries but continue to survive and thrive may also point to the ineffectiveness of the poison.
- Sacrifice – Drink the poison.
- Clever Dad – Work out where Shaun is being held.
- Trial Master – Complete all five of Ethan's trials successfully.
- Since poison can affect people differently depending on their weight, metabolism, overall health, and several other factors, the Origami Killer would have found it nearly impossible to choose a poison that would kill Ethan and other fathers in exactly one hour without having any debilitating symptoms leading up to that hour (which would be needed to ensure they'd be able to save their sons). This may be a hint that the drink isn't actually poisonous and is part of a test. (Then again, that conclusion may be premature from the perspective of the first-time player as this is already a fictional world where the high-tech ARI exists.)
- A glitch can occur in this chapter, in the scenario where Ethan does not have all of the letters to the address. If Ethan listens to the video on the phone three times, a glitch can occur after Ethan puts the phone down where the phone will appear by the steering wheel and the audio from it will keep playing, as though Ethan were still holding it.
- This chapter will be skipped if:
Chapters played as Ethan (in chronological order) - Prologue | The Mall | Father and Son | The Shrink | The Park | Where's Shaun? | Paparazzi | Lexington Station | The Motel | The Bear | The Butterfly | The Lizard | Fugitive | The Shark | On the Loose | The Rat | The Old Warehouse
Chapters played as Scott (in chronological order) - Sleazy Place | Hassan's Shop | Suicide Baby | A Visitor | Kramer's Party | The Golf Club | Manfred | Eureka | The Cemetery | Flowers on the Grave | Trapped | Face to Face | Hold My Hand | Origami Killer
Chapters played as Norman (in chronological order) - Crime Scene | Welcome, Norman | Kick Off Meeting | Nathaniel | Covered Market | Shrink and Punches | Jayden Blues | Under Arrest | Mad Jack | Fish Tank | Solving the Puzzle | The Old Warehouse