Forty years after Picasso’s largest painting,, Le Train Bleu, was sold, a museum finally has the space to show it. The 33-foot-by-33-foot canvas will be the centerpiece of an autumn exposition at the Victoria & Albert Museum about Serge Diaghilev, the Russian man who reinvented ballet in the early 20th century. Picasso helped design nine of Diaghilev’s company’s ballets; Picasso’s Le Train Bleu, which he painted in 1924, features two women and was the front-cloth for a ballet of the same name. It was purchased in 1968 by collectors who never had the space to show it; except for a handful of fundraisers and a weekend fair, it hasn’t been on show since its purchase. The V & A acquired the painting in 2007; the Diaghilev exhibit with Le Train Bleu opens in London September 25.