- Otto Tyler: I didn't think Sam Mayo was proven guilty beyond a reasonable doubt.
- Mike Hammer: Oh Otto, Otto, in the face of all that evidence...
- Otto Tyler: Circumstantial evidence.
- Mike Hammer: All right! That wasn't enough for you, huh?
- Otto Tyler: To send a man to his death? No!
- Mike Hammer: You're not dealing with a man, Otto. You're dealing with vermin, dirt, lice...
- Otto Tyler: But he wasn't on trial for that!
- Barney Green: Those private detective credentials aren't a hunting license and there's no open season on Sam Mayo!
- Mike Hammer: You better knock it off, city boy. There's never a closed season on varmints.
- Mike Hammer: Now listen to me, Mayo. The cops have to use one hand on you because they have to hold the book in the other, but I can use two hands!
- Sam Mayo: You're barkin' up the wrong tree.
- Mike Hammer: Maybe! But I'm about ready to stop barkin' and star bitin'.
- Mike Hammer: You know, O'Dell must be a pretty special customer if you serve him after hours.
- Rita: Who says I did?
- Mike Hammer: You says you did. You told the police that you served Jack O'Dell dinner here between the hours of 9:30 and 10 o'clock on April 16th.
- Jack O'Dell: Get off my back and stay off, Hammer.
- Mike Hammer: What happens if I don't?
- [pulls a pistol from his holster]
- Jack O'Dell: This could make a pretty big hole in your future, Hammer.
- [last lines]
- [although Mayo shot Otto in self-defense, Mike discovers the pistol Mayo used was the one used in a previous murder]
- Otto Tyler: I don't know why I went after Mayo.
- Mike Hammer: Don't worry about it, Otto. You were right all the time. Mayo was innocent of that murder. You got what you came for... but then, so did I. So did I.