The National Gallery of Art presents 'I Spy: Photography and the Theater of the Street, 1938–2010,' on view in the West Building from April 22 through August 5, 2012. The exhibition is devoted to street photographs by some of the genre's greatest innovators: Walker Evans (1903–1975), Harry Callahan (1912–1999), Robert Frank (b. 1924), Bruce Davidson (b. 1933), Philip-Lorca diCorcia (b. 1951), and Beat Streuli (b. 1957).