Edward Hopper's art, through his wife's eyes

Nighthawks, 1942 Hopper’s most famous painting. Three customers in a late-night diner are all lost in their thoughts. In the sketch, the densely drawn pen-and-ink lines of the street outside increase our focus on the bright sliver of diner-wall inside.

Edward Hopper's paintings often depict isolation. But as a new book of his sketches reveals, the artist had an unsung − and sometimes waspish − collaborator: his wife.