In 1835, the San Cristobal Island located somewhere in the British West Indies is ruled by sadistic beauty, Lady Susan Walker, who forces the local men to join the black slaves on her sugar cane plantation and either work or die. She's always dressed in black and never lets go of her whip, the black snake. Her latest husband has gone missing making her a real black widow. Her right hand man, impotent, racist and violent Joxer Tierney, is in command of the slaves and he makes sure that they hate him even more than they do her. Young slave Joshua plans a revolt, but his religious father Isaiah is terrified of what might happen if the revolt fails. Sir Charles Walker, the brother of Susan's late husband, goes undercover as Ronald Sopwith to investigate what really happened to his brother. She hires him as the plantation accountant, gives him a black sex slave named Cleone and eventually tries to seduce him. Her sadistic gay assistant may no more about Charles' brother's fate.