Unreal II is the sequel to the original Unreal and takes place in the same fictional universe - but the main player character and the locations are different than those found in the first game.
As the player, you are the lone representative of the Law in a distant sector of space. You patrol your beat in the creaky but serviceable starship Atlantis, a former military escort vessel that was decommissioned and retrofitted for civil government service long ago. You are accompanied by a support crew of three: Ne'Ban is your trusty alien pilot, Isaak is an engineer who keeps the ship running, and Aida acts as your Intelligence officer - she monitors the situation in the sector, keeps you up to date, and briefs you before you leave the Atlantis to go on a planetary mission.
Things are quiet... until the sector erupts in a full-scale interstellar war. Battles rage on and around more than ten vastly different worlds as several alien races, multiple mercenary armies, and the infamous Terran Military engage in fierce combat. You are caught in the middle of the fighting, and must balance your responsibility to protect the colonists, archaeologists, miners, and other civilians in your sector... with the duty to discover the source of the conflict and put an end to the war.