Last season’s Fringe finale left a lot on the table as far as the overarching universe goes, but was also a satisfying series conclusion if FOX chose not to renew the show. Thankfully FOX has decided to give Fringe one last season in which to wrap up all of its nagging plotlines, and to give back-story on one of TV’s more mysterious characters: The Observers.

In the newest trailer for Fringe season 5 we are treated to something fans have only dreamed of: a peaceful Bishop family picnic – that is, until the Observers arrive. A previous teaser for the season had suggested an Observer “arrival” was imminent, but seeing the event unfold is even more harrowing.

At the center of it all is Peter and Olivia’s daughter Etta – who fans know grows up to become her own version of a Fringe agent – but here is only about six or seven. Whether this is the moment Etta (full name Henrietta) is separated from her parents is unclear, but there’s a certain sense that something bad is about to happen.

Included in the teaser are also brief looks at a few of the season’s tantalizing shots, as well as an exchange between Walter (John Noble) and an Observer that leaves us fearful for the genius scientist’s life. It isn’t the first time we’ve experienced Walter in some sort of danger, but seeing his face bloodied like that illuminates just how connected we’ve become to these characters. More importantly, it shows that rather than simply watch and document, the Observers will become willful and violent participants this season.

Fringe‘s fifth and final season, while only 13 episodes long, promises to be its most explosive and explorative yet. Last season we were only briefly treated to a post-Observer invasion world, but now we hope to see how that all comes to be.

Like Fringe season 3’s penultimate episode and finale, there was a chance audiences were being introduced to a time period/universe that wasn’t set in stone, but the way in which that season 4 episode, ‘Letters of Transit,’ played out left us aching for more. And that’s just what fans are going to get: a whole lot more Observer back-story, a vision of Olivia and Peter’s future, and hopefully a satisfying conclusion to a show that has pushed the boundaries of serialized television.

What do you think will happen in Fringe season 5? How would you like to see the series come to a close?

Fringe season 5 premieres September 28th at 9pm on FOX.