Cordell Walker, is a former dolphin trainer with an elite Force Reconnaissance unit and a modern-day Ranger who believes in the Code of the Old West.
On the reservation, the young Cordell lived a hard life, especially with some peers who bullied him, until one day, Billy Grey Wolf intervened and defended Walker causing the two to become "blood brothers".
As a Texas Ranger, Walker opposes vigilantism, yet thinks nothing of bending any regulations which complicate his own pursuit of a criminal.
Despite his physical skills and moral soundness (expanded in the Chuck Norris Facts), which shows in most of the episodes, is sometimes saved or at least helped by his partner Trivette or other characters.
In the episode, "Vision Quest", Walker falls into depression momentarily after losing his eye sight courtesy of a bomb, and upon learning the damage could be permanent, considers resigning from the Rangers, until Chief White Eagle and Alex help him to adapt to his disability until his eyesight returns.
Walker has some occasional romantic rapports in the early seasons of the series, such as in the episode "The Right Man at the Wrong Time" where he falls in love with a singer, and defends her from her ex-husband, and also hit by a veterinarian in a veterinary leg confiding uncle Ray.
"Days Past" reveals that Walker was about to get married ten years prior, but his girlfriend Ellen Garrett, was killed in an ambush set up by criminal Vince Pike.
In later seasons, he develops feelings for, dates, becomes engaged to, and ultimately marries the deputy district attorney Alexandra "Alex" Cahill.
In the series finale, the Walkers welcome their first child: daughter Angela, whose name is a possible nod to Norris's 1988 movie Hero and the Terror.
However, in the episode "Till Death Do Us Part", in which Walker ends up in a coma and his friends recall some of their greatest memories of him, it turns out their first meeting had taken place during a riot: while trying to calm the crowd, Trivette was ambushed and nearly killed, but was saved by his future partner.
Walker's gruff character makes it difficult with their initial partnership, and Trivette is forced to work hard to gain his respect and trust, but they later become good friends.
Being quite touchy, he is sometimes the butt of jokes by Walker or CD or Alex, or is involuntarily involved in comic situations of various kinds.
He also had faced several legal problems, such as in "Trust No One" in which he is accused of having pocketed part of the spoils of a robbery, and in "The Hands of God", where he seemingly injured a little boy during a shootout, and in both cases, Walker never lost his faith in his partner, and Trivette is ultimately proven innocent at the end of both episodes.
On other occasions, Alex is taken hostage by criminals to lure Walker into a trap, but she usually remains unharmed because the rangers save her regularly, sometimes helped by other characters.
On the other hand, Alex was shown care Walker during times that he was injured, helps him and the other Rangers by providing them with warrants, mandates, and permits.
This passion for feminism is variously explained in the series: In one episode Alex said that her friend was killed by her partner in a dispute, while in "Texas vs. Cahill", she was forced to admit that her ex-boyfriend, under the influence of drugs, had assaulted her years earlier.
Much of the story so far reported is told by Lucas Walker in double episode where the ranger takes custody of an orphan child.
He died of a heart attack while in the Indian reservation; reappears in a few episodes in which Walker recalls and recounts his childhood, played by another actor but as a young man.