The characters are in the Saturn system when Firewall contacts them. Another investigation has noticed something very unusual, a smuggled antimatter warhead with quantum entanglement control. Tracking the warhead leads to Phelan's Recourse and various subcultures, eventually pointing at a remote moonlet and its Brinker inhabitants. Arriving there the characters the chaotic remnants of an AI experiment gone wrong. A powerful seed AI is loose and the characters better figure it out before they accidentally unleash it across space.
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