Captain Hikaru Sulu took the USS Excelsior near the Klingon border after cataloging gaseous anomalies in Beta Quadrant. Suddenly, the moon Praxis exploded. The explosion opened a vortex in which the Seltorian Astro Carrier emerged. Captain Sulu went to Red Alert and opened hailing frequencies. He said "This is Captain Hikaru Sulu of the USS Excelsior. Identify yourselves." The Seltorian commander said "We are the Seltorians. We come from the same galaxy as the Tholians and the Neo-Tholians." The Seltorian commander told Sulu that the Seltorians were once slaves of the Tholians, but they rebelled against them and they wanted revenge on the Tholians. Captain Sulu told the Seltorian commander that they were in Klingon space and that the Seltorians needed to get to Tholian space to get revenge