Running along the western border with Pakistan and stretching for nearly 30,000 square kilometers, Barmer is one of India's largest parliamentary constituencies by area. This vast of land also includes tracts of the Thar Desert and amid the searing heat of the area, the battle for Barmer in the 2019 Lok Sabha elections is haunted by ghosts of 2014 - old friendships gone sour, bitter political rivalries and the desire to settle scores for past wrongs.