It keeps you guessing as to how Chris survived. The guilt feeling of Dave. The feeling of the crew, etc. To remain in the area and not leave Chris. The IT engineer on figuring how to isolate and reboot the necessary program. Even as the audience was leaving the theater there was the speculation as to how Chris survived 29 minutes without oxygen and come out alive and no brain damage. My friend and I thought of amphibians hibernating in the winter. I highly enjoyed the movie.

Brilliant execution with audio visual effects. Allows the audience to feel the race against time and understand the urgency of the situation.

This was a great movie.

It was good. And to think about the very dangerous job those people have to do.