This month marks 40 years since Michael J. Fox, as Marty McFly, jumped into a souped-up DeLorean and went back in time, putting his very future existence at risk. (SOUNDBITE OF FILM, "BACK TO THE ...

Time travel movies are a staple of the sci-figenre, but they can often be over-complicated at best and nonsensical at worst. Some science fiction movies take too long to explain the fundamentals of ...