The Musée d'Orsay is the second most-visited museum in France after the Louvre. In 1986, this former Paris train station became a showcase for Impressionist art. The exhibition rooms are constantly evolving because only half the paintings are on display at any one time; the others are kept in the storeroom. Curators regularly renew the exhibits. Sometimes, the masterpieces require the expert care of restorers, who then have the delicate mission of bringing the paintings back to life. We take a closer look.