The story begins by introducing George, Harris, Jerome and Montmorency, a fox terrier. The men are spending an evening in J.'s room, smoking and discussing illnesses they fancy they suffer from. They conclude they are all suffering from 'overwork' and need a holiday. A stay in the country and a sea trip are both considered, then rejected after J. describes the bad experiences had by his brother-in-law and a friend on sea trips. The three decide on a boating holiday up the River Thames, from Kingston upon Thames to Oxford, during which they will camp, notwithstanding Jerome's anecdotes about previous experiences with tents and camping stoves.