The book is mainly written in third person narrative from Tad's point of view, but also contains epistolary segments, consisting of letters from Cissie to her friend Ketty, towards whose home they are travelling.

After his mother died in childbirth, he was taken in by his overbearing aunt, who treats him as an unpaid servant, existing only to be bossed around and humiliated by Mr Jackson, the lodger, and Esther, the hired help.

She, Tad and Khush set off on a journey West, towards the Nebraskan home of a friend from the travelling show, Ketty, with Mr Jackson and Esther in hot pursuit.

A kind old widower helps them on their way by disguising Cissie as a boy and giving them a boat in which to sail down the Ohio River with Khush.

Khush does not take kindly to his confined quarters on the small flatboat and, a few days into their journey, pitches himself and Tad into the river.

The group's elders agree to take Tad, Cissie and the elephant to the large port of Cairo if Khush shows that he wants to go with the two youths.

However, Khush again becomes impatient of his dark, cramped surroundings rocks the barge, forcing the Captain to make them disembark 200 miles from Cairo.

When Tad sees a sign on the riverbank that Cissie and Khush have disembarked secretly, he goes ashore to meet them, leaving Esther and Mr Jackson sailing past their prey.