The way the characters try to manipulate one another is handled horribly throughout. Consider the scenario when someone is attempting to capture photos of important evidence at a crucial moment. The entire scene is (inadvertently) amusing to watch. Silly things like the prior example detract from the narration's suspense. It is not felt till the very end. A thriller cannot afford to be devoid of exciting moments. The entire first half serves only as a prelude to the intermission when the real action takes place.
Here, the hero makes the connection to the main plot and his quest formally starts. It is plainly done and very predictable. Comparatively speaking, the second half is superior because it contains the true twists, turns, and thrills. But the screenplay gives the whole thing a rather predictable appearance. The approach a cab driver takes to the investigation lacks the fervor and vigor to keep one on the edge of their seat.