In the upper left corner of one of the most recognizable paintings in history, a pencil inscription reads: could only have been painted by a madman. For over a century it was assumed to be vandalism. Infrared scans proved Edvard Munch wrote it himself. This episode traces the biography of The Scream from its origin on Ekeberg Hill above the Oslofjord in January 1892, where an exhausted Munch saw the clouds turn blood red and felt an infinite scream passing through nature, near a slaughterhouse and the asylum where his sister was a patient.

We weigh the competing explanations for that sky, from the 1883 Krakatoa eruption to nacreous polar stratospheric clouds to a straightforward panic attack, and we correct a common misreading: the original title, The Scream of Nature, reveals the figure is covering its ears against the sound, not making it ...