The Escape Ladder, 1940 by Joan Miro

As German occupying forces threatened France, Miró took his family to live into the relative haven of Palma on the island of Mallorca. It was here that he made his Constellations series in 1940-1941. Miró had spoken of the "deep necessity that makes him take part in social upheavals, that attaches him and his work to the heart and flesh of his neighbour and makes the need for liberation in all of us a need of his own".

These musical all-over paintings have textured smoky backdrops on which shapes are drawn from Miró's repertoire of symbolic forms dance and move about. Art historian tracks the complexity of their genesis and how they are connected to Miró's wartime experiences - in The Escape Ladder, 1940, the swooping birds symbolic of bombers over Spain and the desire to escape.