A man wakes up naked, disorientated and lost in a dark cave. He's cold, hurt, and has no idea what brought him there, nor what happened to the dead man next to him. Surrounded by the ruins of an ancient underground world, hounded by ravenous wild creatures and evil phantoms, Tolbiac struggles to regain his memory as he winds his way to the surface through a network of tunnels and laboratories and begins to unearth the deep mystery behind the ancient organizations that owns the tunnels, Eden Log.