The drinking party at Medius’ in Babylon on 31 May 323 b.c., marking the onset of Alexander’s terminal illness, is explored from contemporary and later texts. Close reading of fragments by Nicobule and Aristobulus, set beside the reticence of the court daybooks (Ephemerides) and the studied vagueness of secondary sources, clarifies in detail the sequence of events. Justin, Plutarch and the author of the Liber de morte Alexandri cast light on the silence imposed by the King’s successors. A narrative emerges of the day itself, the spread of rumour, the two false explanations for Alexander’s death that were successively propagated, and the third explanation, most probably correct, that Aristobulus was first to publish.