If it weren't for the Jake Gyllenhaal's presence, I probably wouldn't have watched this movie. And I say that, because science fiction is not a genre I like, so I only watched it because of Jake. Fortunately, this movie also involves mystery (and that was the point that excited me) and I didn't even know it, since I tried not to read the synopsis. It is a film that manages to intrigue, right in the first scene, the audience is as confused as the protagonist. The doubts are already implanted and, each time he returns to the events on the train, new pieces are revealed. I was immersed all the time and, as much as the ending makes room for different interpretations, I still liked it. The concept of "source code" is complex, I think I would have to watch it several times to understand it better.