Quarantine is a contained thriller where the concept is everything:
“A television reporter and her cameraman are trapped inside a building quarantined by the CDC after the outbreak of a mysterious virus which turns humans into bloodthirsty killers.”
Cool idea. It offers plenty of intrigue and creepy atmosphere (and at a reasonable cost). But as I watched it, I wondered:
Who are these people?
The characters are flat. I know what their jobs are, but that’s about it. There is a missed opportunity in building deeper connections, particularly between the protagonist (Jennifer Carpenter) and her cameraman (Steve Harris). Why do they never share their hopes, plans, or passions? The only character development is from calm to hysterical.
Additionally, the protagonist becomes less interesting and less active as the story progresses. At the start of the story, she’s cordial with mildly sexist firemen to try and get a better scoop. Then, when the crisis begins, she pushes back against authority to keep filming. But by the third act she is nondescript and reactive.
One of the strengths of a contained setting is it can drive character development. My favorite example of this is The Shining. Jack Nicholson’s descent into madness is driven by his containment.
Avoid concept tunnel vision by making sure your characters are interesting without your great concept. Then, make sure they galvanize as a result of your concept.
Screenwrite Now 