3. Z For Zachariah (2015)
Compared to some of the actress' other movies, Z For Zachariah weirdly — and rather unfortunately — didn't get as much attention and notice as it deserves. Even despite the fact that it starred a trio of high-grade talent, including Margot Robbie, Chiwetel Ejiofor, and Chris Pine. The muted, quietly engaging character piece, centered around a small group of people after a nuclear apocalypse, gives these tremendous actors a lot of room to show off their acting prowess, and that's certainly an opportunity they live up to. But, it's notably Margot Robbie, in the lead, who gives one of her strongest, most underrated performances to date as Ann Burden, a humble, deeply complex and nuanced character.