Overview: Ann, the survivor of a nuclear apocalypse, lives a simple, pleasant life of solitude until two men enter her life and her Eden is destroyed. Roadside Attractions; 2015; Rated PG-13; 97 minutes.

The Obligatory Part Where I Compare It to the Book: When I read the book by Robert C. O’Brien last year, I was disappointed. I had high hopes for a story that seemed far up my alley, the novel being a character study with a post-apocalyptic backdrop. But I didn’t like it. I couldn’t connect with the characters. Their actions were confusing and frustrating. By the end, the book was quiet in an anti-climactic way. And the movie from director Craig Zobel is quiet too, but graceful in its subtlety. Rather than feeling dull or stilted, it feels natural. Still, even with its cozy verisimilitude, there’s an underlying tension that never goes away. The movie, like the book, feels as if it’s building towards something big. Fortunately, the film (which diverted so far from the book that it’s almost unrecognizable) delivers.

The Cast: It might seem like a poor decision to cast the bombshell, Wolf of Wall Street-scene stealer Margot Robbie as a backwoods farm girl, but I’m as surprised as you are to report that she pulls it off beautifully, and a big part of my love for this movie came from Robbie’s performance. Z for Zachariah does something that most movies can’t or won’t attempt: It paints faith as a positive and admirable thing. Ann is extremely religious, but she isn’t judgmental. She prays before meals and spends her free time playing a church organ, but she accepts Loomis’ lack of belief as valid and worthwhile. She’s a lovely character who is strong in her own theology without being pushy, and much of that is thanks to Robbie’s performance. But it’s Chiwetel Ejiofor who steals the show. With Z for Zachariah, Ejiofor has confirmed my suspicions that he’s one of the best actors working today. Ejiofor is unbelievably good. He can convey ten conflicting thoughts with one look.

Enter Chris Pine: Ejiofor and Robbie were so natural and engaging on screen, I was disappointed to see Chris Pine join the film halfway through as Caleb, a good old country boy whose intentions never seem fully golden, though in an entirely superfluous supporting role. Caleb raises the tension, but I’m not sure we needed him to. The movie becomes something else entirely; it’s less of a dance between two compassionate, yet fundamentally different characters, and more of a conventional love triangle, which is a shame, as had Z for Zachariah stayed the course, it would’ve been an absolute gem.

Overall: Even with its weaknesses, Z for Zachariah is a charming movie. It’s exquisite in its portrayal of faith and forgiveness, it features great performances, and at times it’s as good a character study as any you’ll ever find.

Grade: B+