Sam Spade is hired by Miss Wonderly to find her sister who has run off with a man named Floyd Thursby. But the mysterious and alluring Miss Wonderly is actually none other than the dark Brigid O'Shaughnessy, and when Spade's partner is murdered while on Thursby's trail, Spade finds himself suddenly both hunter and hunted: can he find the precious falcon, a treasure worth killing for, before the Fat Man finds him?