In a few specific years across the 20th Century, the proportion of boys born mysteriously spiked. We follow one researcher’s obsessive quest to find out why. And next, a tale of science and skulduggery. Michael Mann was a respected climate scientist, unknown outside of a small academic circle, until he produced a graph that shocked the world and changed his life forever. Hannah Fry explores two tales of data and discovery. Producer: Ilan Goodman