The Man on the Box is a humorous romantic adventure by Harold MacGrath, first published in 1904. The novel follows Lieutenant Bob Warburton, a charming and mischievous soldier, who finds himself posing as a coachman to get closer to the woman he loves. As he navigates through a series of comedic misunderstandings and thrilling situations, Warburton becomes entangled in espionage and political intrigue. MacGrath's witty dialogue, lighthearted romance, and action-packed plot made this book a popular early 20th-century favorite, and it was later adapted into both a play and a film.