Z for Zachariah

How do you make a convincing post-apocalyptic drama on a shoestring budget? In the case of Z for Zachariah, you write a character-driven script that takes place in the wilderness.

Plus, this emotionally grounded adaptation of the science-fiction novel by Robert O’Brien showcases complex performances by three established stars that help to compensate for some thin plotting and narrative contrivances.

It takes place in the aftermath of a nuclear war, when Ann (Margot Robbie) lives on her family’s farm in an idyllic valley that’s sheltered from toxic radiation. Her solitary routine is interrupted when she encounters Loomis (Chiwetel Ejiofor), a scientist who she nurses back to health. Despite their religious differences — he’s an atheist and she insists on preserving the family chapel on their land — they shack up together.

There’s an unsettling vibe as their relationship deepens because their motives remain cloudy, especially when a third traveler (Chris Pine) arrives seeking food and shelter, threatening to change the sexual dynamics between them.

The screenplay gradually reveals character details, including secrets that both men are trying to conceal about their past. Ann isn’t as passive as she first appears, and Robbie’s portrayal nicely mixes strength and vulnerability.

The landscapes are both beautiful and harrowing, even if the second half of the film veers into more predictable love-triangle territory that squanders some of the provocative ideas introduced at the outset.

More talk than action, the film from director Craig Zobel (Compliance) mostly dispenses with the visual effects and futuristic gadgets you might expect in such a story. In fact, details are scarce in terms of time and place, and the context of what happened to wipe out humanity (there are scattered hints, but in the end, it’s not that important).

Instead, this is a more demure and introspective approach to being the last people on Earth. It’s a survival tale at its core, only less about resourcefulness and perseverance than it is about how desperate circumstances challenge our moral compass and our belief systems — such as notions of faith, compassion, forgiveness, and trust.

Such concepts are examined without resorting to heavy-handed lectures, even if the film’s set-up is more compelling than its payoff.

Rated PG-13, 98 minutes.