Chapter 27, which opens with Tom’s belief that his adventures were only a dream, prepares us for the dreamlike quality of the novel’s conclusion. Before Tom and Huck find out about Injun Joe’s treasure, St. Petersburg seems a safe, sleepy town with year-round summery weather perfect for children’s make-believe and games. However, once fantasy adventures of piracy and Robin Hood turn into real encounters with outlaws, murder, and stolen treasure, Tom and Huck seem well prepared to handle the scenario precisely because of their many rehearsals. Although much of the novel concerns Tom’s gradual acclimation to the adult world, the surprising plot twist brought about by Tom and Huck’s discovery of Injun Joe’s plan seems to reaffirm their childhood activities and to suggest that these imaginative activities should not be abandoned as soon as adult responsibilities emerge.
Twain has already poked fun at church, school, and Sunday school, so his unveiling of the Temperance movement’s hypocrisy—the “Temperance Tavern” serves alcohol in a secret room—follows naturally. Because the novel focuses on Tom’s journey toward adulthood, and because Twain views the adult world as hypocritical and pretentious, it can be argued that Twain views Tom’s maturation as an unfortunate loss of freedom and honesty. However, Twain seems to be redefining the concept of maturity. Whereas conventional understanding links maturity with adulthood, Twain distinguishes between real maturity—the kind Tom displays when he testifies against Injun Joe and saves Becky from punishment—and the false maturity of the Temperance Tavern and the Sunday school. The older townspeople may be more learned than Tom by virtue of their age, and thus more intellectually mature, but Twain makes no similar correlation between age and moral maturity.
When Tom leaves Huck by himself to handle Injun Joe because he is excited by the prospect of picnicking with Becky, he behaves immaturely and gets himself into trouble. In Chapter 30, we find out that Tom and Becky haven’t actually gone to the Widow Douglas’s house; they are lost in the cave. The stage seems set for a final confrontation between Tom and Injun Joe at the Widow Douglas’s, but Huck, not Tom, is to prove the hero. Tom has been the planner all along, persuading the reluctant Huck to go along with his schemes. By staying when Tom irresponsibly leaves for the picnic, Huck finally assumes control of the Injun Joe plot and proves his superior maturity.