On the Saturday afternoon of February 17, 2018, most of Sydney was enjoying the beach weather. But Andy Corner, the chief financial officer of Big Un, was urgently reviewing a draft document sent to him and the board of directors by lawyers at DLA Piper.

Corner, a lean middle-aged Englishman, had a habit of injecting an overly cheerful tone into his emails. But he must have had a sense that the situation was turning dark.