Captain Raffi Musiker and her crew aboard the U.S.S. Endeavour are trapped beneath the ever-hardening icy surface of an eyeball planet, desperately searching for an artifact hidden below. Beyond their ship lies inky darkness and the occasional glimpse of something monstrous moving in the void. Despite the danger, the captain drives her crew onward at the behest of Sybil, a superintelligence wearing the face of one of Starfleet’s most trusted officers. Without the artifact, Sybil claims, Starfleet faces total annihilation.Officer D’Vana Tendi is convinced Sybil is leading them straight to Hell. Raffi desperately needs that not to be true. Meanwhile, the rest of the crew remain unaware that their mission was initiated by artificial intelligence.Thanks to Sybil, the crew of the Endeavour is only one day away from either survival…or destruction.