Fiona Bruce and Philip Mould investigate a lovely landscape painting, purported to be by one of the forefathers of impressionism and one of the most important artists of the 19th century, Jean-Baptiste-Camille Corot. Its owner, Sally Green's late husband, bought it in the late 70s, primarily for the impressive frame. He was always intrigued by the painting and wondered if it was genuine. Sally is now on a mission to finish what he started. However, the painting was turned down by the authority on Corot, so the team will have to find new evidence to help persuade them to change their mind. A lot is at stake. If the work is genuine, it could be worth £70,000. If not, just a few hundred.