He and two other Ferengi assisted Ulis in pillaging the Enterprise NX-01 after rendering its crew unconscious.
After being awakened by Tucker, who was unaffected by the anesthetic used by the Ferengi, T'Pol was able to convince Muk that Ulis was trying to rob him of his share of the profits. Later, Tucker was able to lead him, Ulis and Grish through a maze of corridors on the ship until they came to what Tucker claimed was the ship's vault, where the Ferengi's greed led them to an ambush by T'Pol.
Upon recovering, Muk and the other Ferengi were forced to carry all the items they had loaded onto their own ship back aboard the Enterprise. They were then allowed to leave aboard their vessel, with Krem, the Ferengi who was treated with disrespect by the others, now in command. (ENT: "Acquisition")