A fellow teacher and the victim's secret husband. He is revealed as the murderer who killed Halloran after a slow poisoning attempt failed, ultimately committing suicide when cornered.
Secretly married couple whose union was concealed from the public.
Competing suspects with overlapping motives involving Louise's affection and wealth.
Donahue serves as bait in a hospital trap to catch Stevens.
School head who employs Stevens as a faculty member.
Explore the full interactive character relationship map of Murder on the Blackboard