Kill them all is a linear narrative game where you play a mercenary who will be deployed on Serenity Island. The island is facing a serious epidemic and does not have the military capabilities to manage the situation properly. You will be mandated to carry out various missions.

The title says it all 

Kill infected, escape from runners, empty the rest of your magazine on riot-infected

Upgrade your equipment and HQ, and craft what you lack with the money you earn and the resources you find.

But don't be too bold, there will always be something stronger than you.