Excerpt From This Week's Column

...I’ll come out of a time travel movie going, “yeah, but wouldn’t…” For instance, say someone a character goes back in time and changes something. Wouldn’t the character in the present suddenly not remember anything that had happened in the first version of the past?

Or say a character in the future decides to change something in the past. Say John Conner in the future (The Terminator) decides to send someone into the past. He knows he has to do this because his mother told him he had to, right? So he sends back Reese to protect his mother so that he’ll be born. Reese ends up being his father.

Okay, but Reese couldn’t have been his father the first time through, else he wouldn’t be there to send Reese back in the first place. The first version of the future had to play out before the second version of the past in order for there to have ever been a first version of the future. Follow me?

From there, you get into the argument that the past wasn’t really changed. John Connor was still born, just not in the same way. The same things occurred but because of different catalysts.

This is the kind of thing I always end up thinking about when I come out of a time travel movie. The inconsistencies. The what-ifs. The does-it-really-works.

Most of them, I don’t think, work. The first, and maybe only, movie that worked to my mind was Déjà Vu. And that only worked because you got to see the effects of the changed past correcting itself in the future. Like the loop closed or something. That movie had this “Ah ha!” ending. Loved it.

Premonition, on the other hand, didn’t make sense to me. Or if it did, it was just an uninspired kind of sense. But it had inconsistencies from go. Make no mistake, however, it’s a time travel movie, much in the same way Groundhog Day was...