Being able to watch all 4th season episodes sequentially without a week's delay greatly improves the continuity. Peter being erased from the timeline and then returning isn't nearly as disruptive as when broadcast (when I hated it). While Season 3 was the best, Season 4 was a close second. The writers' success at repeatedly coming up with strange adventures which mirrored the emotional journey of the core characters while advancing the 'mythos' made for some of the best sci-fi I've ever seen. Why is it so rare to have characters we care about along with fascinating ideas about technology that together make us ponder what it means to be human? My only wish is that the story telling had jumped to the Observer War (Season 5) sooner and gotten a full season, or more, of it.

After three seasons, we finally get to know more about Astrid! And, I must say, it was worth the wait. However, the beginning of Season 4 is hard to follow because of the timeline shift. Also, I was hoping that the series would eventually return to the original Fringe Division because I liked the characters (and their personalities) in this team and felt that they deserved some type of ending to their story.

Peter disappears after using the bridge machine to save both universes in the fourth season of Fringe. The parallel universes decide it would be beneficial to coordinate all of their Fringe Unit investigations. Peter unexpectedly returns but no one, including Olivia or Walter, recognize him or have any memories of his existence. In the meantime an evil mastermind has created new hybrid shapeshifters that can take the place of anyone. The evil mastermind also begins developing technologies that will collapse the two parallel universes and create a new universe. The fourth season of Fringe includes a focus on the lead characters and their dopplegangers and that provides significant insights into their backgrounds and personalities.