- Muriel Arrowsmith: You had your revenge. Why don't you kill me? Kill both of us.
- Dr. Stephen Arrowsmith: You, I will kill you, you tart, you. You and your filthy friend. But death, my dear, must come to you only after I've torn from your bodies all the suffering and pain a human being can stand, and you don't know yet how long it takes to die of pain.
- Muriel Arrowsmith: You're a monster.
- Dr. Stephen Arrowsmith: [to Muriel Arrowsmith] I've asked you before not to come down to my laboratory while I'm busy with my experiments.