The dramas of Eugene O'Neill--often called America's first "serious" playwright--exhibit an imagining of the natural world that enlivens the plays and marks the boundaries of the characters' fates. O'Neill's figures move within purposefully animated natural environments--ocean, dense forest, desert plains, the rocky soil of New England. This new approach to O'Neill's dramas explores these ecological settings as crucial to his characters' ability to carry out their conscious and unconscious desires. O'Neill's career is covered, from his youthful one-acts, to the middle years experimental dramas, to the mature tragedies of his late period. Special attention is paid to the connection of ecology and theological quest, and to O'Neill's persistent evocation of an exotic, natural "other." Combining an ecocritical approach with an examination of Classical and philosophical influences on the playwright's creative process, the author reveals a new, less hermetic O'Neill.