Redstone by Cari Z

Kyle Foster thought he was doing the right thing when he saved Cody Helms’ life at the Academy, but now he’s paying the price. Shunted to the worst prison in the Alliance, Kyle’s chances of survival are slim. That is, until Isidore Cain steps in.
Isidore is a survivor, but he’d never have made it this far without friends. To repay his debt, Isidore must infiltrate the notorious Redstone prison and save Kyle’s life. But it won’t be easy.
As Isidore navigates the treacherous prison and faces unimaginable challenges, he begins to question if he can really pull off this dangerous mission. With the odds stacked against them and everything on the line, will Isidore and Kyle make it out alive?