In Streets of Laredo, Larry McMurtry completes the story of Captain Woodrow Call. As he is dying, Gus McCrae in Lonesome Dove warns his friend Call that their time has passed. In Streets of Laredo, McMurtry takes up Call’s story some twenty years later. Captain Call is a legend in the West, a hero honored for helping make the border region of Texas and Mexico safe for settlers. The legend hides the reality that Call is now a bounty hunter, hired by the wealthy capitalists that he once despised. The legend also obscures the fact that Call is a small, frail, old man who removes the trigger guard from his rifle so that he can get his swollen, arthritic fingers on the trigger.

The story opens in San Antonio, when Call is hired by a railroad owner to hunt down Joey Garza, a train robber and psychopathic killer. Calls summons his old comrade, Pea Eye Parker, who farms in the Texas Panhandle and who is married to Lorena Wood. Pea Eye refuses to join Call. After thirty years of responding to Call’s every order, Pea Eye stuns Call by placing his family ahead of his loyalty to the captain.

Word quickly spreads through the Rio Grande valley that Captain Call is hunting Garza. Tension mounts along the border as people wonder where the killer will strike next. Pea Eye Parker feels guilty for leaving Call to face Garza. He moves south to join Call. Shortly after this, Lorena learns that Call is not only chasing Garza but also facing Mox Mox, a crazed sadist who burns his victims alive. Lorena, terrified, rides south to find her husband. Meanwhile, Call, alone, attacks Mox Mox and his seven gang members. He kills six and wounds Mox Mox, who slinks away to die.

Call joins up with Lorena, and they make their way toward Pea Eye. Then, because of his failing eyesight and a moment of careless inattention, Call walks into an ambush. Joey Garza shoots him three times. Call is near death, and Lorena amputates his leg and carries him out of danger. A doctor later removes Call’s right arm.

Garza besieges Pea Eye, and the old farmer draws on his courage to do what no one else has been able to do. He charges into the crazed killer’s gunfire and inflicts wounds that eventually would have killed Joey, who makes his way home to Ojinaga, Mexico, where he dies in a final explosion of violence.

Order is restored to the border region, largely by the efforts of a woman and a farmer, Lorena and Pea Eye. Lorena brings the crippled Captain Call back to the Panhandle. Call becomes a silent recluse, living in a little cabin near Pea Eye and Lorena. The legendary Texas Ranger earns his keep by sharpening knives and scissors.