From 2261 to 2268, Cyrano Jones earned a marginal living as a trader buying and selling rare merchandise. Among his wares, Jones pawned articles such as Spican flame gems, Antarean glow water and tribbles. Four months before stardate 4523, Jones was in the Klingon sphere-of-influence.
In 2268, Jones was present on the Federation Deep Space Station K-7 during the Klingon plot to control Sherman's Planet, having arrived on the station aboard his merchant starship, the Spacematic. He was responsible for the station's infestation with tribbles, which he was sentenced to clean up or face a twenty-year prison sentence for transporting a dangerous lifeform off its native planet. His sentence was expected to take 17.9 years, which Kirk cuttingly suggested can best be considered "job security" for the massiveness of the task. (TOS: "The Trouble with Tribbles"; DS9: "Trials and Tribble-ations")
In 2269, while on the Klingon planet, Jones acquired a genetically-engineered Klingon tribble predator called a glommer, which he claimed under space salvage laws. He escaped the planet in a one-man Federation scout ship and was pursued by a Klingon battle cruiser commanded by Captain Koloth for causing ecological sabotage to the planet.
The USS Enterprise rescued Jones and a number of tribbles from his scout ship moments before the Klingons destroyed it. Kirk immediately arrested Jones for breaking the law for transporting animals proven harmful as well as for three violations of Federation mandates and forty-seven local ones. Jones, however, declared that they were safe tribbles that he had genetically engineered for compatibility with humanoid ecology – they were incapable of reproducing.
Koloth contacted the Enterprise demanding they turn over Jones and the glommer, noting that they were even prepared to go to war if they had to. Kirk refused until Koloth explained that they needed the glommer Jones stole in order to grow more of them so that they could rid the Klingon planet of the tribbles Jones had sold on it, before it became completely overrun.
Jones was played by actor Stanley Adams, who was one of three returning guest stars to portray the same character in both their original and animated appearances.
According to an early draft of "The Trouble with Tribbles", available in David Gerrold's The Trouble with Tribbles, Cyrano's full name was originally Cyrano Day Jaymin. On the name, Gerrold noted that "[he] did not like this name at all when [he] wrote it, but [he] had not realized that the name Jones was once again available for this story." The mini-bio that appeared in this draft of the script drew Cyrano in a slightly different light than he ultimately became:
"Cyrano Day Jaymin is a planetary scout. He locates planets for the Federation and is paid by the Federation according to the intrinsic value of each planet he reports. Most planets are gas giants like Jupiter, but still there are a great many Earth-type planets in the galaxy that need locating.
The situation is roughly akin to gold-mining in California in 1840. Cyrano's success as a locator is evidenced by the fact that his clothes have an air of well-used shabbiness about them – but they are still flamboyant and colorful. He is a sort of faded swashbuckler."
The novella "Honor in the Night" depicts an alternate universe where Cyrano Jones and his tribbles were all killed by an explosion on board his vessel while it was docked at K-7 in 2267. The explosion was caused by an accidental overload in the ship's impulse drive. Consequently, Arne Darvin's sabotage of the grain quadrotriticale was never discovered (since there were no tribbles left alive to expose him), and the poisoned grain was shipped to Sherman's Planet, where it cost the lives of thousands of colonists.
The alternate reality version of Cyrano Jones appears in the Star Trek: Ongoing story arc Legacy of Spock. He is approached by Ambassador Spock on Deep Space Station K-7 to request transport to Romulus to discover the Empire's plans for eliminating the surviving Vulcans.