A Pre-war man regains consciousness within the confines of a Vault-Tec Vault, stripped of all memories of his arrival. As he uncovers the vault's haunting mysteries—secrets that entangle both its vanished inhabitants and possibly his own past—he must navigate the treacherous landscape of a devastated world. Each decision he makes ripples outward, reshaping the fate of the surrounding wasteland. Can he piece together the truth before it consumes him? And what consequences will his choices unleash upon those who survive beyond these steel walls?