Ambrose Monk: Adrian.
Adrian Monk: I'm with you, I'm right here.
Ambrose Monk: Tell me who did this.
Adrian Monk: Ssh. It doesn't matter.
Ambrose Monk: It matters to me. I don't want to die without knowing. Tell me, Adrian.
Adrian Monk: Okay. Here's what happened. His name is Paul Gilstrap. He wanted to kill his wife. He worked in a laboratory where they made tetrachlorodrine. A few days ago, he snuck in there and he stole some of it. Ambrose, I met his wife when I went trick-or-treating with Julie. And she said that she ate a Neptune bar every night before bed. Gilstrap poisoned her candy. But he couldn't poison just one. He wanted to make it look like there was a serial killer on the loose, so he had to poison a lot of other candy bars. Put them back into circulation.
Ambrose Monk: So his wife would just be another victim.
Adrian Monk: That's right.
Ambrose Monk: It's a good plan.
Adrian Monk: But he made a mistake. He got caught trying to put the poison back.
Ambrose Monk: Ruined everything.
Adrian Monk: That's right. It ruined everything. Because now if his wife or anyone else died from tetrachlorodrine, they'd know it was him. So he was desperate. He had to get all of the poisoned candy bars out of circulation. He found them all except for two.
Ambrose Monk: Right.
Adrian Monk: The armored car driver had one. He had already taken a bite. If the driver just dropped dead, Gilstrap knew there'd be an autopsy. So he had to think fast. He grabbed the driver's gun and shot him repeatedly. Who would bother looking for poison in a guy who had been shot five times?
Ambrose Monk: Which left just one candy bar. The one I ate.
Adrian Monk: That's right. He's been trying to get it back all night.