Neil Patrick Harris credited as playing...
Billy (Dr. Horrible)
- Penny: You're not really interested in the homeless, are you?
- Dr. Horrible: No, I am, but... it's a symptom. You're treating a symptom while the disease rages on, consumes the human race. The fish rots from the head, so they say. So I'm thinking, why not cut off the head?
- Penny: [pause] Of the human race?
- Dr. Horrible: It's not a... perfect metaphor.
- Dr. Horrible: [after describing about the freeze ray failure] Captain Hammer threw a car at my head.