Casey gets another, arguably even better one in "Svengali": she makes a deal with a famous murderer who thinks of his killings as "works of art" to testify against one of his "fans" in a murder trial. The "artist" sandbags his testimony and plays up the drama to the hilt, which results in a huge scene in the courtroom involving the defendant — but Casey thought he might pull that sort of stunt, so she prepared a special "thank you" for the testimony:
Casey: [approaches Morton as he leaves the courthouse in chains] Well, you were great.
Robert Morton: Did you like it? Bet you didn't know what was gonna happen next.
Casey: You put on quite a show. You got her off; she's going to a psych ward.
Morton: Is that a frown on your pretty face?
Casey: Actually, I think Cecilia is going exactly where she belongs. And so are you.
Morton: [smirking] You're backing out on the deal.
Casey: No, you're being transferred to a federal prison.
Morton: [looking surprised] I thought you'd be a sore loser.
Casey: [smiling smugly] You're gonna love Florence SuperMax: 23-hour lockdown, no visitors, no mail, no phone calls — no human contact for the rest of your life.
Morton: You can't do that to me!
Casey: Why don't you wave bye to all of your fans?
Morton: We made a deal!
Casey: And it's a masterpiece. How do you like my work?