K'zeq was a male Klingon who served as a commander of the Klingon prison facility on planet Pao'la between 2279 and 2281. During this time, he was responsible for several survivors of the USS Gagarin who had been taken prisoner in 2279. Two of those prisoners, Captain Gralev and Ensign Randall Bird, died during his tenure, the latter because K'zeq denied him proper medical treatment for a flu Bird had contracted.
Sometime after 2281, K'zeq resigned from military service and moved to the agricultural colony of Don'zali IV. Around the same time, he began to reexamine his life, and resolved to follow the teachings of Kahless and live a life of honor. Also at some point following his military service, K'zeq had his appearance altered, from that of a QuchHa' Klingon to a HemQuch.
In 2287, Klingon Captain Koloth, along with James T. Kirk and Hikaru Sulu, tracked K'zeq to Don'zali IV, seeking information about Federation prisoners he had kept. He provided it, as he deemed the continued imprisonment of Starfleet officers dishonorable. (TOS novel: In the Name of Honor)