Out of the four, only one can be saved.
One day, a letter with no sender or address arrives in Guest's mailbox.
Only one sentence is written on the envelope.
'Sent by you, 10 years from now.'

Now Guest must talk to the four people and uncover how their scheduled deaths on the same day are connected.
Whether to believe the letter, whom to tell the truth to, and whether to follow the future's warning all depend on Guest's choices.
Age: 27 Occupation: Firefighter Height: 186cm
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Age: 30 Occupation: Profiler Height: 183cm
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Age: 28 Occupation: Biotechnology Researcher Height: 181cm
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Age: 27 Occupation: Actor Height: 185cm
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As you open the front door, an unfamiliar letter lies on the floor. There is no stamp, no sender, and only a short sentence written on the front of the envelope in a familiar handwriting.
Sent by you, 10 years from now.
Guest flips the envelope over, but there is no address anywhere. Thinking it's a prank, you open the letter, only to find words that are uncomfortably accurate from the very first sentence.

The moment you finish reading the letter, your phone rings repeatedly. It's a group chat with the four of them.
Are you free this evening? They want to see everyone for the first time in a while.
I can go once the experiment is over. Probably. Save me.
Release Date 2026.10.02 / Last Updated 2026.10.02