Leck was a Ferengi entrepreneur and a professional eliminator. Unlike most Ferengi, however – he was more interested in honing his combat skills than in earning profit. Perhaps his best skill was knife-throwing.
Leck gave potential clients specific instructions to contact him only via a secure channel.
In 2374, Leck was recruited by Quark to join a team of Ferengi commandos that were trying to rescue Quark's mother Ishka from the Dominion. Leck eagerly joined for the opportunity to test his skills against the Jem'Hadar. However, although he claimed he had no interest in gold-pressed latinum, he also hated being cheated – as Quark tried to do by telling the team that there was only a twenty-bar reward, when in fact Zek had promised 50 bars.
Upon the successful conclusion of the mission, Leck commented to Quark, "This is the sloppiest, most amateurish operation I've ever seen... If you ever do something like this again, count me in." (DS9: "The Magnificent Ferengi")
"I hope this is a secure channel?"
"I followed your instructions to the letter."
"Very good. Who do you want eliminated?"
"I don't care about latinum."
"I thought you said you didn't care about latinum!"
"I don't! I just don't like to be cheated!"
- - Rom and Leck, after everyone finds out that Quark lied about the Nagus's reward. (DS9: "The Magnificent Ferengi")
"How do we know these schematics are accurate?"
"No need to stand on formalities here - call me Leck."
"No, I meant you should call me 'sir.'"
"Don't be ridiculous."
"You mean 'don't be ridiculous, sir'"
"This is the eighth run-through and you haven't even hit a single Jem'Hadar. And you shot Moogie!"
"I could see that we weren't going to rescue her - so I put her out of her misery."
"I've never seen a sloppiest, more amateurish operation in my life... If you ever do something like this again -- count me in!"
Leck appears in the Worlds of Star Trek: Deep Space Nine, Volume Three story "Satisfaction is Not Guaranteed", in which, in the year 2369, he undertakes a mission that leads him to Terok Nor. It is there where he meets Quark, who happens to have a Deltan holosuite program that Leck has been after for years. Leck also successfully assassinates a Romulan Tal'Shiar operative and several Nausicaan guards. Furthermore, in late 2376, Leck is hired to break into the Glat Archive and find evidence that a marriage contract between Grand Nagus Rom and Prinadora had not been dissolved. Leck found the mission extremely difficult, but also a great challenge. He managed to infiltrate the facility posing as a Torf and download the contract.
Leck also appears in the "Victory is Life" expansion to Star Trek Online. In the mission "Quark's Lucky Seven", something of a sequel to "The Magnificent Ferengi", Leck joins Quark, Nog, and Brunt in a mission to infiltrate an Iconian dreadnought to reclaim the Sword of Kahless, in order to convince the Klingons to join the war against the Hur'q. Leck becomes annoyed as he overloads power conduits to eliminate the Iconian Herald crew, as there are no explosions; he finally creates one himself by overloading a phaser pistol and walking away from the explosion unfazed as he dons a pair of futuristic sunglasses, in reference to a popular film cliché. Leck's distinctive throwing knives are a weapon reward from the mission.