After a deadly virus is unintentionally released from a research lab in the UK, twenty-eight days pass, leaving a handful of survivors in London fighting for their lives. This lethal contagion, transmitted by both animals and humans, transforms its victims into violent, uncontrollable beings, making containment a distant hope. As chaos reigns, the group's struggle for survival intensifies, forcing them to confront not only the infected but also the challenges of their own humanity.