Time travel has a self-correcting mechanism called slippage, moving time travelers either in time or place from their target in order to protect history. Ned arrives at the correct time, but unknown to him, he is not at the estate where another time traveler should meet him. Instead, he has slipped in destination to a railway station 30 miles away. He meets Terence St. Trewes, a besotted young Oxford undergraduate, mistaking him for his time travel contact. He agrees to share the cost of a hired boat for a trip on the River Thames from Oxford down to Muchings End, where Terence hopes to meet his love, Tocelyn "Tossie" Mering. Ned, Terence, Cyril the bulldog and Professor Peddick (an Oxford don) travel down the Thames navigating locks, beautiful scenery, crowds of languid boaters in no hurry to get anywhere, and the party of Jerome K. Jerome, a homage to the original novel from which "To Say Nothing of the Dog" draws its name and themes.