Letek was a Ferengi who served under DaiMon Tarr in 2364. Letek was part of Tarr's crew that participated in the theft of a T-9 energy converter from Gamma Tauri IV. Letek later beamed down to a planet in the Delphi Ardu system with Mordoc and Kayron when their Marauder was immobilized above the planet by a powerful force field.
Letek and the others had agreed to search for the source of the energy field in conjunction with Commander William T. Riker and other crew members of the USS Enterprise-D which had been similarly captured. However, once on the surface Letek and his party attacked the Enterprise landing party. Later, when the source of the field was discovered to be a Portal of the Tkon Empire, Letek attempted to negotiate with the Portal by offering to destroy Enterprise if his own starship were released. (TNG: "The Last Outpost")