This particular module consists of five scenarios or "mini adventures". WotC seems to think each of those should run in about an hour each. In my experience, they take about an hour and a half to two hours each. The setup for the adventure overall focuses on the rantings of a madman. Somehow, the players realize he is actually prophesying, and they turn that into clues that lead to five separate scenarios. That felt really weak, but I ran with it anyway because, with a public group, we didn't really have time for an in-depth "session zero" to get the group together. I would have liked a better introductory hook.
The scenarios themselves vary. Without getting too far into spoiler territory, the first two felt too much alike: go to a farm and discover a mystery, then halfway resolve it by trying to be heroes. (That first scenario nearly led to a TPK - some of the demonically-affected creatures can present a significant combat challenge!) The third scenario felt even more disconnected from the overall storyline. However, I really liked running the fourth and fifth, and the reactions of the players (especially to scenario four) indicated that they really felt immersed: creepy stuff was happening and they had to work to figure out how to resolve things.
Grabbing it and making it your own will allow you to deal with that rough setup, which is mostly just a problem in the way the AL set up this particular content. Therefore, I wouldn't recommend running this as an adventure. Think of these instead as five encounters (or maybe just the last two) that you can drop into your campaign to foreshadow some great evil stalking the world or just to set the tone with demons and undead and cultists.