Twain uses a frame story, a story within the story, as a literary device. The novel is framed by a contemporary setting in 19th century America, where the narrator, Hank Morgan, works in a munitions factory and gets involved in an accident. This frame story provides context for the main narrative, explaining how Hank is transported back in time to the era of King Arthur. The novel's initial narrator introduces the reader to Hank Morgan, who tells the narrator his life story. The narrative the reader follows is a manuscript "written" by Hank. At the end of the novel, this is revealed again when Hank makes the following statement in Chapter 43:
I finished turning my old diary into this narrative form; it only required a chapter or so to bring it down to date.
Twain's use of a frame story allows modern readers to connect with the narrator. Hank's voice and perspective are relatable to the readers of Twain's time, which helps bridge the gap between the contemporary audience and the historical setting of King Arthur's court. This relatability makes the time-travel concept more accessible to readers.
The frame story also importantly provides a platform for Hank to express his satirical critique of the social, political, and religious systems of both eras. Through Hank's observations and comparisons, Twain satirizes various aspects of society, including monarchy, feudalism, and chivalry.
