As told by Vicki Constantine Croke in '' The Lady and the Panda , '' in 1936 , shortly after her husband 's death in China , and with her entire -LRB- albeit minor -RRB- inheritance at stake , the 35-year-old Harkness -- '' mad as a hatter , '' according to her brother -- boarded the liner American Trader to Shanghai to begin a panda-hunting expedition .