For his part, Riley is full of praise for Stewart’s performance.
“Kristen was hired before Twilight I think but it took that long for this film to come to fruition. Before that she’d worked with Jodie Foster, Sean Penn had chosen her, a lot of people with a lot of knowledge of the business had hired her for the actress she is.
With Garrett [Hedlund] as well, the system at the studio tends to mean only certain types of film are made, which then pigeonholes actors as eye-candy. But it’s not true. They [Stewart and Hedlund] don’t have anything to prove to their colleagues but they have something to prove to elements of the media or the industry that pigeonholes them. I think Kristen is great in the film.”
Source | Via