From last chapter…
"I didn't do it?"
Skipper pinned Private against the stone wall. "Why did you kill Rico?" he demanded.
"Skipper, I-"
"What did you do with Kowalski? TELL ME!"
"I didn't kill him! Please, I'm just a boy. Do you really think I would do it?" Private was shaking.
Skipper released him. His breathing was hard and ragged, his eyes were wide with shock.
"I suppose not. But why was the knife in your hand?"
"The lights went out, and I heard Kowalski scream. Then I heard Rico scream and then someone slipped a knife into my hand. And then… the lights came on. And then I realized I was holding a knife. Then you started yelling at me."
Skipper wiped some sweat off his brow. "On your feet, Private. We're going to find that murderer."
Meanwhile, deep in the sewers, the killer watched, twirling a cigar. "Try, Skipper. Try."