LONDON — Filmmaker Alex Garland wants Civil War, a tense thriller about a group of journalists documenting societal collapse as they chase a scoop in a conflict-torn United States, to be a conversation starter.

Set in the near future and both a war film and a road movie, Civil War sees fictional Reuters photographer Lee (Kirsten Dunst) and reporter Joel (Wagner Moura) take to the road with the aim of reaching Washington, DC, before it falls to a rebel faction.