Emperor Staleek is the leader of the Scarran Empire. He first appears in the "We're So Screwed" three-part story in season 4, holding a conference at the secret moon of Katratzi. It is there that he first encounters John Crichton. Crichton comes to Katratzi under the guise of selling the information he has on wormhole technology to the highest bidder. Crichton is truly there to rescue Scorpius, whom Staleek has prisoner at the base. During that time, Staleek hopes to find a way to capture Crichton without setting off the nuclear bomb attached to Crichton's belt. He is also under the impression that Scorpius is his spy and double agent, but in truth Scorpius turns out to be a triple agent whose true allegiance it to the Peacekeepers. When Crichton severely damages the Katratzi base, Staleek orders Captain Pennoch to Earth, as he has learned from Crichton that the planet contains a large supply of the crystherium flower, vital to the Scarrans' power. Pennoch's mission fails and his ship is destroyed by Crichton and Aeryn Sun.

Staleek later takes an active role in the Peacekeeper/Scarran War, traveling in his flagship the Decimator. He personally captures Crichton at Arnessk and is later present at the battle over Qujaga where Crichton unleashes a wormhole weapon and forces the two sides to make peace. Staleek's reluctance to agree to peace goes further than Grayza's, but he concedes just in time to save himself, later signing the settlement with Grayza.