28 Weeks Later is a 2007 post-apocalyptic horror film directed by Juan Carlos Fresnadillo, who co-wrote the screenplay with Rowan Joffé, Enrique López Lavigne and Jesus Olmo. It serves as a standalone sequel to 28 Days Later (2002), and is the second installment overall in the film series of the same name. The movie stars Robert Carlyle, Rose Byrne, Jeremy Renner, Harold Perrineau, Catherine McCormack, Mackintosh Muggleton, Imogen Poots, and Idris Elba. It is set after the events of the first film, depicting the efforts of NATO military forces to salvage a safe zone in London, the consequence of two young siblings breaking protocol to find a photograph of their mother, and the resulting reintroduction of the Rage Virus into the safe zone.

28 Weeks Later was theatrically released on 11 May 2007, in the United Kingdom and United States by 20th Century Fox and Fox Atomic, respectively. The film received positive reviews from critics and grossed over $65 million worldwide. A sequel, 28 Years Later, is scheduled for release on 20 June 2025.