In this first color version of Mark Twain's classic novel Tom is punished, runs away, is presumed dead, testifies in a murder trial, and saves his girl-friend.
Aunt Polly (May Robson) learns that Tom Sawyer (Tommy Kelly) played hooky from school and punishes him. Tom has to white-wash the fence, but he lets other kids help for gifts. Tom throws the bucket of paint on Sid Sawyer (David Holt). Tom is engaged to Amy but gets rid of her and tries to impress Becky Thatcher (Ann Gillis) by walking on her fence. Tom trades a frog for Bible tickets and is awarded a Bible, but he says the first two disciples were Adam and Eve. In school Tom takes the whipping for Becky's drawing, and she terms him noble. Tom asks Becky to be engaged, and she agrees until she learns he was engaged to Amy.
Huckleberry Finn (Jackie Moran) tells Tom how to cure warts with a dead cat. At night Tom sneaks out and goes to the cemetery with Huck. They see Injun Joe (Victor Jory) knock out Muff Potter (Walter Brennan), kill Doc Robinson, and put the knife in Muff's hand. Huck and Tom swear not to tell. Tom gives his medicine to the cat. Aunt Polly hits Tom, and he leaves. Becky throws Tom's gift back. Tom plays pirate with Joe Harper (Mickey Rentschler) and Huckleberry. They see men dragging the river for them. Joe and Tom miss home. Tom sneaks in and sees Polly and Miss Harper (Margaret Hamilton) mourning. Tom hears Polly praying and kisses her. At the funeral Injun Joe threatens Muff to stay hid. Joe, Tom, and Huck watch the service and then walk in. Tom tells Polly that he dreamed he saw them but then admits he was there.
Muff is arrested for killing Doc Robinson. In the trial Injun Joe says that Muff stabbed him; but Muff's lawyer has no witnesses. Tom and Huck take tobacco to Muff. Tom testifies as Injun Joe brandishes a knife and throws it at him. Injun Joe runs out. Tom is honored at a picnic. Tom and Becky go in the caves, run from bats, and get lost behind a cave-in. Aunt Polly and others realize that Tom and Becky are in the caves and search. Tom and Becky hear them, but more caving in occurs. Becky cries for her mother, and Tom comforts her. Tom gives Becky the end of his string and goes down a tunnel. Tom finds money but then sees Injun Joe and runs. Tom climbs up and knocks Injun Joe down to his death. Becky screams; but Tom leads her to the light and climbs out. Then he goes back for Becky. In the final scene Tom is acclaimed a hero and throws cake in Sid's face.
In the prolog Mark Twain says that he wrote this so that adults will remember their childhood. This film helps audiences to realize how punishment may be unjust and counter-productive, as boys often need some space to explore their unfolding world. Tom is mischievous but also heroic.