An experienced eastern constable comes to Texas to show the Texas Rangers how modern police techniques can be used to do their job better. He doesn't help his case by stating most Texas Rangers are dirty and untrustworthy.
Arailroad man and his beautiful daughter who are old friends of Chad arrive in Laredo to offer Chad a job and maybe a wife. Joe and Reese with some help from the Captain try to prevent Chad from leaving the rangers.
Billy Harker's girl friend Laurie leaves Chad undressed and afoot while he is on Billy's trail. Joe and Reese are sent after Chad but Laurie gets the best of them until Joe decides to let Laurie take them to Billy without her knowing.
As punishment for fighting the rangers are sent to escort a wagon of buffalo hides. They add some female company to the trip not realizing they are caring a load of rifles being illegally sold to the Comanches.
Captain Parmalee sends Reese to Red River to pick up a shipment from St. Louis. Reese says a little too much on his way out of town. With rumors of a gold shipment coming into Laredo, Reese is being stalked by criminals.
Laredo is visited by a state senator who is held up on the stage with Parmalee. The rangers try to make amends but digger a deeper hole with the senator ultimately taken hostage when the rangers try to fake his kidnapping and rescue.
The rangers capture the Slaughter gang and the money they stole. The gang breaks out of jail and the money is stolen while the rangers and others attend a show put on by a lady of culture who Reese helped sell tickets.
Cletus Grogan is convinced he's a jinx because disaster follows him everywhere. When Joe is captured by bank robbers, and his fellow Rangers appear to be in a crossfire, Reese pretends to allow Cletus to rescue him to break the curse.
The Army challenges the rangers to fight on July 4 but the Pryor gang stealing silver from a local mine is messing with their plans. The rangers scheme to get their man in the ring while the boss of the ring has a surprise for the rangers.
The Rangers are told to stay in Laredo but Chad and Joe scheme to go to San Gill not knowing Parmalee is there. Reese follows once he learns what they did but true to form all three get into trouble but manage to save Parmalee's life.
Chad and Joe routinely take advantage of Reese. When a payroll is stolen by a group lead by French officers, they con Reese into spying on the them. His actions put him in front of a firing squad for which the men tell him he won a medal.