TNT's Steven Spielberg-produced sci-fi actioner 'Falling Skies' didn't make the biggest landing in its initial 10-episode run summer 2011, but the alien invasion thriller did turn enough heads to warrant a second batch of 10 episodes, set to debut sometime this summer.  But a whole year later, what mysteries do we need to remember?

Thankfully, TNT and TV Guide have us covered in plenty of time for the summer premiere of 'Falling Skies' season two, which encapsulates the bigger lingering mysteries with their new video "Unanswered Questions."  In it, executive producers Remi Aubuchon, Greg Beeman, Bradley Thompson, David Whettle as well as writers and directors behind the series take a look back through the first season for the bigger questions to be tackled by 'Falling Skies' Season 2.

We know very little about the elusive Skitters, how they connect to the biological harnesses they attach to children of resistance or what's going on with those tall, skinny aliens who seem to be controlling them from behind the scenes.  And on top of all that, what's their plan for the remaining human survivors, Tom Mason (Noah Wyle) in particular?  Where did he go after being whooshed away in their craft at the end of season finale "Eight Hours?"

For those unfamiliar with the series, 'Falling Skies' follows former history professor Tom Mason as one of the leaders of a human resistance force desperately struggling to fight back and survive in the aftermath of an alien invasion that killed off 90% of the planet's population.  In addition to protecting his children, Tom maintains a close relationship with the resistance's doctor Anne Glass (Moon Bloodgood), as well as charismatic rogue John Pope (Colin Cunningham) and military leader Captain Daniel Weaver (Will Patton).

With Tom abducted and the survivors on the move for Season 2, what new mysteries can we expect to unfold in the aftermath of the Skitter invasion?  Check out your refresher course in the video below, give us your own theories in the comments, and check out the second season of 'Falling Skies' this summer on TNT!

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