When Wiseman turned his attention to London’s National Gallery, he characteristically eschewed commentary, instead letting tour guides, docents, and even dancers, interpret its masterworks. He moves behind the scenes to reveal the work of curators, conservators, and administrators as they balance the challenges of running an institution while preserving the opportunity to contemplate art. The importance of the latter is beautifully underscored “in the relay of gazes that finds us looking at museumgoers looking at portraits that look right back—at artists, art lovers and moviegoers—even as Mr. Wiseman, that sly old master, looks at all of us in turn”