It's springtime in Charleston, and just about every species of South Carolina flora and fauna is in bloom during the annual Spring Plantation Ramble. While tea shop owner Theodosia Browning serves Dragonwell sweet tea, guests mingle, enjoy flower shows, and bid at a rare plant auction. Festivities come to a screeching halt, however, when commodities broker Mark Congdon is high bidder for a rare monkey-face orchid, then promptly drops dead. It looks like a simple heart attack, but Theodosia suspects otherwise and looks for answers in the nearby Nightshade Garden.