Here is when Spooner tells what happened about his past in Weekenders Adventures of I, Robot.
Calvin: They said at the precinct you were in an accident.
Spooner: I appreciate you stopping by. But you know I might not be alone in here.
Calvin: I told you not to drive by hand. You're not gonna believe this. Sonny has a secondary system that clashes with his positronic brain. It doesn't make any sense. Sonny has the Three Laws. But he can choose not to obey them. Sonny's a whole new generation of robot. A robot not bound by those laws could do--
Spooner: Anything. All right. Iook. whatever's going on down at USR. that robot is the key. And I need you to get me inside to talk to it again. Doesn't look like much. but this is my bedroom. I....
Play. On. Run? End program. Cancel. It doesn't feel good. does it? People's crap malfunctioning around you. Detective. I didn't... ...understand. That's how you knew Lanning. May I? Hand. Wrist. Humerus. Shoulder. The entire left arm. One. two... ...three ribs. No. they.... That one's me. Oh. my God. A lung? USR Cybernetics Program. For wounded cops. I didn't know any subject-- Anybody was so extensively repaired. Well. take it from me. read the fine print on the organ-donor card. It doesn't just say what they can take out. It says what they can put back in. Lanning did it himself.
Calvin: What happened to you?
Spooner: I'm headed back to the station... ...normal day. normal life. Driver of a semi fell asleep at the wheel. Average guy. Wife and kids. You know. working a double. Not the devil. The car he hit. the driver's name was Harold Lloyd. Like the film star. No relation. He was killed instantly. but his I never really met her. I can't forget her face. though. Sarah. This was hers. She wanted to be a dentist. What the hell kind of 1 2-year-old wants to be a dentist? The truck smashed our cars together... ...and pushed us into the river. I mean. metal gets pretty pliable at those speeds. She's pinned. I'm pinned. The water's coming in. I'm a cop. so I already know everybody's dead. Just a few more minutes before we figure it out. An NS-4 was passing by, saw the accident and jumped in the water.
NS-4 Robot: You are in danger!
Detective Del Spooner: Save her! Save the girl!
Detective Del Spooner: [End of flashback]] But it didn't. It saved me.
Dr. Susan Calvin: A robot's brain is a difference engine, it must have calculated-
Detective Del Spooner: It did. I was the *logical* choice. It calculated I had a forty-five percent chance of survival. Sarah only had an eleven percent chance. That was somebody's baby. Eleven percent is more than enough. A human being would have known that. But robots, nothing here. [points at heart] They're just lights, and clockwork. But you go ahead and trust them if you wanna.
Calvin: I don't understand. Lanning wrote the Laws. Why build a robot who could break them?
Spooner: Hansel and Gretel.
Spooner: Two kids Iost in the forest Ieave behind a trail of bread crumbs.
Spooner:To find their way home. How did you grow up without Hansel and Gretel? -Is that relevant? -Everything I'm trying to say to you... ...is about Hansel and Gretel. If you didn't read it. I'm talking to the wall. Just say Lanning's locked down so tight. he couldn't get out a message. He can only leave clues. A trail of bread crumbs. Like Hansel and Gretel. Bread crumbs equals clues. Odd. but fine. Clues leading where? I don't know. but I think I know where he left the next one. I think Lanning gave Sonny a way to keep secrets. I think the old man gave Sonny dreams. Are you being funny? Please tell me this doesn't run on gas. Gas explodes. you know!