After discovering that Happyhead was a sinister eugenics experiment, Seb along with a select group of participants, finds himself washed up (literally) on an isolated island called Elmhallow. Here the teens are split into two groups the chosen Ten and the Bottom Percentile. With the boys divided, Seb's burgeoning relationship with Finn is put to the test and when the competition takes a deadly turn, their plan to take down HappyHead rapidly unravels...