Based on a novel by William Wister Haines, two linemen risk their lives working on power towers, and both love the same nurse.
Young farmer Slim (Henry Fonda) asks Pop (J. Farrell MacDonald) to let him be a lineman, and Red (Pat O'Brien) helps him get a job as a grunt on the ground. Red chases gamblers away from Slim. Stumpy (Stuart Erwin) takes Slim to town and meets Pearl. Slim sends money to his aunt and uncle. At a card game Slim sees cheating, and a fight breaks out. Only Red and Pop are left standing, and they leave with Slim.
A lineman falls to his death. Slim is made a lineman and climbs up the tower. Slim drops a wrench, but Red calls it his. Red teaches Slim. In order to protect Pop, Red and Slim won't tell an investigator the man killed was drunk, and they are fired. Red and Slim go to Chicago and find nurse Cally (Margaret Lindsay). While Red gambles, Cally shows Slim how to dance. Stumpy reads a postcard from Slim. Cally asks Slim to give up line-work. Red buys Cally a bracelet as a good-bye present, and Cally asks Slim to write to her.
Red drives fast in the desert. He and Slim are hired and climb wooden poles. Slim stops Wilcox (Joe Sawyer) from tampering with Red's rope. Wilcox pulls a knife; in the fight both are wounded and taken to the hospital. Cally gets a letter from Slim and visits him, saying she is staying. Red comes in, but Cally doesn't kiss him. Red tells Cally he is going away for a month on a job. Cally says she will sell the bracelet to pay the hospital. Slim gets well, and Cally tells Slim she loves him. Steve offers Slim a job, and Slim tells Red he and Cally are getting married. When Slim tells Cally they are going with Red, because Pop needs them, she says she won't marry him if he goes. Slim leaves with Red, and they join Pop and Stumpy. Pop's crew is called out in a blizzard to hot wires. Garrettson (Harland Tucker) quits, because it is too dangerous. Cally arrives at the boarding house, and Garrettson tells her it is 88,000 volts. Cally asks Garrettson to take her there. A rope breaks, and a man is killed. Red falls. Slim sees Cally and learns that Red is dead. Pop and Slim go out to finish the job, and Slim climbs the tower.
This film was dedicated to the workers who help bring electricity to millions, and the story reflects the power projects of the New Deal to bring rural electrification. Red considers his job so dangerous that he avoids marriage, and Cally fears the same problem with Slim. In the end she decides to stay with him anyway, showing how people can become accustomed to dangers.