Widower Gary Farrell can't afford, on his $45-weekly salary as a truck driver, to send his young son, Mickey, to a high-priced military school and decides to enter heavyweight-boxing tournament in an effort to win the $500 prize money. He wins and turns to boxing as a career and, in a short while, and under the guidance of "Pop" Turner, becomes a Contender for the Heavyweight title. Newspaper reporter Linda Martin is attracted to Farrell but he is paying more attention to the flashy Rita Langdon, who introduces him to night clubs, late hours, drinking, roistering and other attractions and distractions. Ignoring the warnings posted by Linda, Pop, Mickey and Biff Benham, his old cab-partner in the truck-driving business, Farrell continues to abuse all the training rules but still wins bout after bout.