Absolutely loved RDJ's performance in this movie. Troubled, charming, and funny all in one. Even in his more subtle moments, he absolutely grasped my full attention.
Furthermore, the use of silence as a way to produce suspense and anxiety was superb. The most gruesome scenes is where silence is heard most loudly, further exacerbating the direness of the scene.
Also loved the interrogation scene. The shots at reading body language, faces of concern and utmost judgement. An absolute masterpiece of an interrogation.