A scene from “Unfinished Business”

Norman Amberson: [after Jessica accuses him of committing the murder] Why would I have done that?

Jessica Fletcher: Was it perhaps triggered by that bill from Vinton's that your secretary insisted on calling your attention to? That was when you learned Elizabeth had purchased an item of clothing for another man. You must've guessed who that other man was. Someone Liz had promised never to see again.

Norman Amberson: Roger Adiano. He's an actor. Not very good. Certainly not successful. Just a boy. Liz was out. I used my key. I thought I was just gonna wait for her, but that wasn't it. That was a lie. I wanted to look around in her things, even though I was afraid of what I was going to find. It wasn't much, just trifles she had forgotten to throw out.

Jessica Fletcher: The program from an off-off-Broadway play. I remember now. It was on the floor near the overturned coffee table.

Norman Amberson: I didn't bother to destroy it. It was meaningless to anybody but me.

Jessica Fletcher: To you, it meant Elizabeth had broken a promise. She'd gone to see Roger Adiano in a play and had probably bought him a gift.

Norman Amberson: I could see them in my mind. Just a flash. Then all the pictures came back of her with all the other men. It snapped, turned right around. I hated her. I hated the woman I loved. Classic. I wanted to destroy her, blot her face out of my memory. I was looking around for something to use on the portrait. I couldn't find my pocket knife. I found the lipstick in my pocket. And when she came in and found me, I could see from the terror in her eyes that ... She ran for the bedroom, and I grabbed the scarf around her neck. I wasn't really aware of what I was doing. Then she was dead, and I panicked.

Jessica Fletcher: And you vandalized the apartment to make it look like she had been killed by an intruder.

Norman Amberson: Survival. Self-preservation. Oldest instinct. Oh, God, I loved her.