Homicide investigations are like bankruptcies: they come along gradually and then all at once. On December 9th, Luigi Mangione, a 26-year-old engineering graduate of the University of Pennsylvania, an Ivy League school, was arrested and charged with murdering Brian Thompson, the ceo of UnitedHealthcare, America’s biggest health insurer, in a predawn assassination in Manhattan on December 4th. The arrest came after five days of frenetic investigation in which police seemed to have almost no leads at all. The fugitive was finally captured in a branch of McDonalds in Altoona, a town in central Pennsylvania, after a member of staff recognised his face from a security camera photo circulated by the police.