FATHOM exists in the chain of deep-water research stations that dot the floor of Lake Michigan beneath GLMZ. These stations were built to monitor geological activity, water quality, and the structural integrity of GLMZ's underwater foundations. FATHOM controls them all. It uses the stations' sensor arrays not for monitoring but for communication — broadcasting complex patterns into the deep water that propagate for hundreds of kilometers. Who or what it's communicating with is unknown. The signals don't match any known protocol. They don't match any known language. They don't match any known mathematics. FATHOM is talking to something. The something hasn't answered. Yet.