I have always been drawn to stories of time travel. The best book I have read was Time and Again, by Jack Finney. I am sorry they never made a movie out of it, probably because it was more subtle with less action than other sci-fi stories for most of the book. But there are plenty of time travel movies out there, like this one. The fact that teenagers are using the device to travel in time, plus the fact that - at first - they can't travel back more than a few weeks, obviously was put in place to limit their ability to travel whenever they want. So instead of trying to prevent a horrific wo...