White Wall (2010) on Netflix

In the near future, everything has changed. Basic human rights have become the rarest of luxuries. No one knows when this started but everyone knows how. The VXII, the deadliest virus ever created, spread like wildfire and decimated the majority of the world's population. The non-infected survivors now cling to life in four quarantined cities behind a wall. Shawn Kors and his brother, Jude, survived the VXII only to grow up in a squalid internment camp for orphaned children. Under the care of the militia, they were pitted against other children in backwoods death matches. Shawn, Jude, and the few who escaped became notorious for their incredible fighting skills. They have since parted ways. Shawn now makes a comfortable living as a janitor at the local medic station. He spends his days dreaming of curing the VXII. When Shawn discovers the discarded body of a fellow internment camp friend, he is forced out of hiding and pulled into a rabbit hole of conspiracy and violence. All signs point to Jude. With bounty hunters and the militia on his trail, Shawn races to find his brother before Jude executes an unspeakable action that will destroy them all. He chases Jude across a sprawling post-apocalyptic landscape to an abandoned laboratory. There he discovers the true nature of his world and the secret behind the white wall.