The flight from Rome had been pleasant enough, even if the business he was on wasn't exactly. His Italian fiancee's father had been kidnapped and presumably murdered, and Fletch is on the trail of a stolen art collection that is her only patrimony. But when he arrives in his apartment to find a dead body, things start to get complicated.
Inspector Flynn found him a little glib for someone who seemed to be the only likely suspect in a pretty clear case of homicide. He wasn't exactly uncooperative, but it wasn't like he was entirely forthcoming either. And Flynn wasn't entirely convinced that the 19th-century Western artist Edgar Arthur Tharp really occupied most of Fletch's thoughts.
With the police on his tail and a few other things to do beside prove his own innocence, Fletch makes himself at home in Boston, renting a van, painting it black, and breaking into a private art gallery - that is, when he's not "entertaining" his future mother-in-law and visiting with the good Inspector Flynn and his family.