Heart and Science turns on the fate of the orphaned Carmina Graywell, who is left in the charge of her aunt and guardian Mrs. Gallilee when her fiance is forced to take an extended trip to Canada's drier climes in order to recover his health. Over the issue of her inheritance Mrs. Gallilee schemes to manipulate, control and ultimately destroy the naive but strong-willed Carmina. The story is complicated by the machinations of Dr. Benjulia, a dark genius whose passionate devotion to the study of diseases of the brain leads him to encourage the progress of Carmina's life-threatening brain illness for the sake of scientific observation; the narrative builds to a pair of spectacularly lurid climactic scenes."