Hundreds of survivors across a century — climbers, sailors, divers, soldiers — report the same thing. At the moment they were about to die, a calm presence appeared beside them.

It gave directions. It knew the way out. It disappeared the moment the danger passed.

A neuroscientist built a machine that can summon something like it. But what his subjects experienced and what survivors describe are not the same thing.

The cases are real. The pattern is undeniable. What the presence actually is — that part is still open.

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