Chesterton's Manalive is a comedic mystery novel following the misadventures of Innocent Smith. Smith, a "holy fool" whose eccentricities become the center of a mystery at a London boarding house.

Manalive is a book in two parts. The first, "The Enigma of Innocent Smith," concerns the arrival of a new tenant at Beacon House, a London boarding establishment. During his first day in residence Smith creates the High Court of Beacon; arranges to elope with Mary Gray, paid companion to heiress Rosamund Hunt; inspires Inglewood to declare his love for Diana Duke, the landlady's niece; and prompts a reconciliation between jaded journalist Michael Moon and Rosamund.

However, when the household is at its happiest two doctors appear with awful news: Smith is wanted on charges of burglary, desertion of a spouse, polygamy, and attempted murder.

The second part, "The Explanations of Innocent Smith," follows the trial. The evidence against Smith consists of correspondence from people who witnessed or participated in the exploits that led to the charges against Smith. In every case, the defendant is revealed to be, as his first name states, innocent.
Gilbert Keith Chesterton was an English prolific and diverse writer whose subjects include philosophy, ontology, poetry, playwriting, Christian apologetics, and fiction, including detective fiction. Chesterton is well known for his reasoned apologetics , as a political thinker and orthodox Christian.