Three friends and their dog embark on a recreational boating excursion up the River Thames, only to find themselves beset by a series of comedic blunders and logistical failures. The narrative follows J., George, and Harris as they attempt to escape their mundane lives in London, only to be thwarted by their own incompetence, the unpredictable English weather, and the stubborn nature of their fox terrier, Montmorency. The story is presented as a first-person account, blending the immediate physical challenges of river travel with lengthy, digressive anecdotes about history, health, and social customs. The world is defined by the late Victorian era, where the river serves as both a literal path and a metaphorical space for the characters to reflect on the absurdity of their surroundings.

Readers frequently highlight the enduring humor of the text, noting that the observational wit remains effective despite the passage of time. Discussion often centers on the balance between the slapstick physical comedy and the author's dry, cynical commentary on the human condition. Critics often point to the episodic nature of the book, which allows for a relaxed, conversational pacing that mirrors the leisurely speed of a boat on the river. Many readers appreciate how the characters' incompetence serves as a vehicle for broader social satire, making the work a staple of lighthearted classic literature. The interplay between the mundane frustrations of the trip and the philosophical tangents creates a unique tone that continues to attract new audiences.