A Kraylor scientist who posed as a ship's doctor carrying vaccines, while his ship was really trying to run an Annari blockade with cloaking technology.
Loken is a member of the crew of a Kraylor ship that Harry Kim takes command of in Nightingale, after its command crew is killed in a battle with the Annari. Presented as the ship's doctor on a humanitarian mission, he works alongside Kim as the young officer tries to lead the vessel, which Kim names Nightingale.
When Loken proves unable to treat injuries, he reveals that the crew are scientists testing a cloaking device to break through the blockade of their world. Kim takes responsibility for the ship anyway and gets it to the planet. Ron Glass played Loken.