I found the opening credits to be brilliant. It gradually introduces a major plot point from a fog of white, resulting in an adrenaline shock of a scene of startling realism.
Unfortunately, the next hour and a half is a slow, painful slog of dialog that thinks it is smarter than it is. It does a good job of riding the line between uncovering a conspiracy and descending into paranoia, but utterly fails to make the possibility of conspiracy interesting or entertaining. The last 15 minutes or so return to entertainment and, indeed, to adrenaline intensity. But the entertaining joy of the beginning and end is not remotely worth the drowse-inducing endurance test that forms the majority of the film.
The violence, the hard truths of parenting and adult life, the potential danger of violence inherent to living, and the internal conflict between obsession and vigilant responsibility make this film inappropriate for viewing by children. The utter failure to engage or entertain for the vast majority of the film make it inappropriate for viewing by anybody.