In the world of Death Stranding, it is understood that the line between the living and the dead is essentially a blurred one, if not a collision of two worlds. BTs, named Beached Things, entities whose souls are from the deceased, and come into existence when that soul fails to cross through the Beach (a corridor or path if you will) into the world of the dead, consequently becoming 'stranded' in the world of the living, with their connection to the other side maintained through an umbilical cord. The bridge between life and death.
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