On stardate 5730.2, the Federation starship Enterprise is on a mission to help decontaminate the polluted atmosphere of the planet Ariannus, when sensors track a Federation shuttlecraft reported stolen from Starbase 4. The craft is disabled and brought aboard along with its strange alien pilot, who is found injured and taken to sick bay. The man later awakens and identifies himself as Lokai, a political refugee from the planet Cheron, who requests asylum. Lokai’s most striking feature is that his skin is half black and half white, the two halves split perfectly down the center of his body. Science Officer Spock remarks that his physiology may be “one of a kind”.