Deep in space, the stealth reconnaissance ship VANGUARD drifts through uncharted territory. On board are Elios, an elite pilot; Teto, a brilliant information analyst; and B.A.I.R.T, a black rabbit-shaped AI assistant. When the crew intercepts an unidentifiable distress signal from deep space, B.A.I.R.T warns them to stay away. Elios changes course anyway. What begins as a rescue mission soon leads the crew toward a black hole that should not exist — and something waiting inside it.