There are things happening here I can't even begin to explain...
- Peter Bishop

That quote, taken from the trailer below, pretty much sums up viewer reaction to the first season finale of Fringe.

There's an alternate reality... in which the Twin Towers exist... and Peter is dead?!?

While the following preview doesn't give away any major Fringe spoilers, it does give fans a nice glimpse of what's to come when the series returns on September 17.

[video url="http://www.tvfanatic.com/videos/fringe-season-two-preview/" title="Fringe Season Two Preview"] [/video]

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.