In “Whispers in the Dark,” an ex-con sells his organs to ensure his brilliant nephew’s future. The boy will grow up to have the highest IQ ever recorded, but the uncle, who sold his eyes, won’t be able to see it. In “Voices,” a history professor becomes addicted to a drug called pulse, which gives him access to a world of vivid fantasy while tearing his brain to shreds. By the time the professor qualifies for a brain transplant, he’s no longer sure what’s real and what’s imagined. And in “Angel’s Island,” a convict in the world’s largest private prison reveals the facility’s chilling secrets.