Two decades before its sequel ‘28 Years Later,’ Danny Boyle teamed with Alex Garland for a dystopian sci-fi flick that featured zombies running after star Cillian Murphy.

The zombie genre has undergone a dramatic transformation over the past two decades, and Alex Garland's work from 28 Days Later to the upcoming 28 Years Later illustrates just how far it's come. What started as a straightforward horror story has become a layered exploration of society,

Days Later’ brought a horrific genre back: the zombies. The movie was two decades ago and starred Cillian Murphy as Jim, who was a bicycle courier guy. He discovers that he is among the survivors of an incurable virus that has wiped out the U.