The Zombie Chronicles: Apocalypse Infection Unleashed Series #1 (Unabridged‪)‬

Val was bitten by a zombie and now she's scheduled for lethal injection. Breaking all the rules, 18-year-old Dean Walters snags an experimental serum. But it can't be tested until Val turns into a zombie: something authorities won't allow. Her execution is scheduled to happen before transformation is complete, giving Dean only hours to break her out. When their helicopter crashes straight into the heart of Zombie Land, his rescue mission becomes a fight for survival - and giving up on Val is not an option.