The Excalibur is called to Mars for a medical symposium on treating the Drakh plague. Irritated at being called away from his important job, Capt. Matthew Gideon finds himself clashing with the officer in charge of security: Capt. Elizabeth Lochley. Lochley herself is in contention with Carr, the Mars-raised officer supervising the situation by Mars.Meanwhile, as the captains clash -- and find themselves rubbing each other the wrong way -- Dr. Max Eilerson wrangles with shuttle pilot Trace over who will escort Dureena Nafeel through the clamor of Mars. Needing neither escort nor the not-quite-friendly banter of the two men, Dureena finds herself forced to defend Eilerson when he runs afoul of an incompetent thief.But Gideon's and Lochley's worst fears seem to be fulfilled when a delegate is discovered dead, murdered by a member of an extremist Doomsday cult. It seems that someone does not want a cure found for the Drakh plague -- someone who has already chosen the next victim to die.