The show mostly demurs on the scandals, the battles with husbands and studio heads, the mistreatment and abuse she suffered. Instead we see how Marilyn Monroe, as a true icon, a venerated idol of the day, came under artistic interrogation. Works by artists from her era and beyond make up much of the second half, and they are mostly awful. Willem de Kooning’s ghastly portrait is a mocking mannequin; her then husband Arthur Miller was furious when he saw it but Monroe sagely said artists should be free to depict her how they wished. With this democratic outlook — one eye on the endless proliferation of her own image — she was essentially Warhol before Warhol.