If you are like so many of us, when you leave any movie that involves time travel, one of the first things you do is try to understand how it all worked.  These thoughts usually run along lines, "If so-and-so did X while traveling, why did the entire universe not implode because…" 

I spend as much time as anyone trying to understand the way the butterfly effect works every time I watch a time travel film, so when I sat down with "X-Men: Days of Future Past" writer/producer Simon Kinberg, the first question out of my mouth was whether constructing a time travel plot  was as difficult as it has always seemed.  Short answer, yes.  Long answer, "Writing a time travel movie is a nightmare.  I would never, ever, do it again unless I absolutely had to."  He then went on to say, "As much time was spent on figuring out the logic of the time traveling in the movie as was spent on any other element of the film."

Simon Kinberg isn't only a producer on "X-Men" films though, he is also helping bring the new "Fantastic Four" to the big screen and, as both movies are in the Marvel universe and being distributed by 20th Century FOX, there is the possibility that, at some point in time, we could see a crossover story.  Kinberg didn't rule it out in our interview,  saying, "It'd be really cool… it happened in the comic books, so there's no reason why shouldn't happen in movies."  He added to that, however, the caveat that there was a lot of groundwork to lay before it could possibly take place.

Watch the above interview, and you'll get a whole lot more depth to those answers, as well as a great discussion of the use of notecards, and some talk of potential standalone (a term Kinberg prefers to "spinoff") movies in the "X-Men" universe.

Directed by Bryan Singer and starring Hugh Jackman, Michael Fassbender, James McAvoy, Patrick Stewart, and Ian McKellen (amongst others), "X-Men: Days of Future Past" opens May 23rd.