Well I have seen all of the episodes except the one about to come on in 16 min. As far as the storyline goes, this is just the beginning to some understanding of a war (which has yet to be really be explained). First, the hunt was on for William Bell, now the hunt is on for Olivia Dunham's memory of the meeting with William. Eventually, I think the show will feature time travel, that will probably deal with the mystery guy. I wanna say that the older Peter Bishop will send the Mystery Guy (Bald Dude) from the future to the past to help his father--Walter Bishop--in the Fringe Department to discover the motive of the "war" (which has yet to be announced). Other than that I love the science ideas that they present, although, I feel like they have been lacking in that department lately.
Just watch the show online, for free, they have all the episodes there.