['Supernatural' - 'Hello, Cruel World']

They walk among us. They look like us. They are dangerous. And they have a plan.

Ladies and gentlemen, the crossover we've all been hoping for has finally arrived: 'Supernatural' has been invaded by Cylons!

All right, technically they're called Leviathans on this show.

So, you've seen the 'Supernatural' season premiere. If you're anything like us, you're probably wondering, What the hell just happened?!

Never fear, because we have more from our group Q&A with Sera Gamble and Bob Singer to shed a little light on the shocking events of the first episode.

Even though the producers were wary of revealing too much about their plans for the season so early on, there are still a few answers here to clear things up a bit.

Join us after the jump for more, and in case it wasn't obvious, huge spoilers for the season premiere ahead!

There's a reason why 'Supernatural' fans refer to the summer break between seasons as "hellatus" instead of "hiatus" -- since May's cliffhanger finale, viewers have been fretting over everything from the fate of Castiel to the fate of Dean's beloved Impala, and the producers have been content to tease for the past four months.

Thankfully, the wait is almost over; the show returns for its seventh season tomorrow night (Fri., Sept. 23 at 9PM) and it's a surprisingly satisfying premiere, managing to tie up many of the loose ends left in the season finale while simultaneously creating more problems for the long-suffering Winchesters to solve.

Hit the jump for our advanced review of the episode, plus highlights from the Q&A that executive producers Sera Gamble and Robert Singer conducted with press on Wednesday. Needless to say, there are light spoilers ahead.