The Oklahoma City Museum of Art features an outstanding collection of postwar American art from 1952 to 1996. This exhibition presents rarely shown works by Richard Pousette-Dart, Ida Kohlmeyer and Leonardo Nierman, as well as artists including Sam Gilliam, Leon Polk Smith, Helen Frankenthaler, Sam Francis, Ellsworth Kelly and Gene Davis. It’s a spectacular compilation spotlighting a period of remarkable creativity in the half-century following the end of World War II — a time when ideas of abstraction and the nature and limits of artistic mediums were being hotly contested and artists continually sought to redefine what painting was and what it could be.