Is Peter already home?

That's the main question/theory espoused by our critic in her review of this week's Fringe return, as "Back To Where You've Never Been" earned a strong 4.8 rating and a heaping of praise from fans around the country.

What's next? Look for the Fringe division to face a powerful adversary on this Friday's "Enemy of My Enemy," one that is back from the grave and at his most dangerous. How so? Get your first look at the episode via the following Fox preview:

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