The Chicago Cubs have been doing badly, and Cap, the coach, must win the pennant to keep his job. His only hope is rookie pitcher Frank X. Farrell, who still hasn't arrived for spring training. When Frank finally does arrive, he has several stories about why he is late. Frank cannot tell the truth about anything, but he is a terrific player and charms Dolly Stevens, Cap's sister-in-law. Dolly and Frank fall in love, but soon she leaves for home. They correspond, and when his teammates tease him about his letters, Frank denies that they are from Dolly. Still, he decides to buy her a ring, but again, he pretends that it is for his sister and not for Dolly. Frank's great pitching attracts the attention of some gamblers. They threaten to break his arm if he refuses to throw the next two games, and to save himself, he agrees. When Dolly returns, Frank manages to ask her to marry him. She accepts, but when she overhears him denying that he really loves her in front of the other ball players, she gets mad, breaks off the engagement, and leaves town. Frank is so unhappy that he loses the next game, but Cap believes he lost on purpose. Cap's wife Bess is convinced that he is only heartbroken over Dolly and promises Frank that she will get Dolly back if he will set up the gamblers. Before he can do that, the gamblers find out he is going to double-cross them and kidnap him. During the game, the Cubs play poorly without Frank. He manages to escape from the gamblers and makes it to the stadium for the ninth inning. Aided by Frank's pitching, the Cubs tie the score. Then Frank hits a home run and wins the game. Frank marries Dolly and promises never to lie again.