"Future Diary" (a direct translation of the Japanese title "Mirai Nikki") is shaping up to be a really awesome series. The story has just the right mix of fast/slow pacing, romance and horror, and a set-up that allows the story to unfold over several volumes while still maintaining the tension.
Volume two starts off almost right after volume one. Yukiteru (The First) and Yuno (The Second) are on a date at an amusement park, where Yuno's obsessive love for Yukiteru both intrigues him and pushes him away. Later, and Yuno's house, Yukiteru's Future Diary leads him down a dark hallway and to a certain door. He knows that he has a choice her to open the door or not, and the future will change either way.
Things take a rapid change of pace, when Keigo (The Forth)'s Investigation Diary leads to the discovery of terrorist bomber Minene (The Ninth) with her Escape Diary in the hands of a cult group called the Church of the Seer who worship a young girl who can see the future and might just be the holder of one of Dues' diaries. Things go from bad to worse when they enter the compound and the arrival of one who calls himself the Hero of Justice (The Twelfth).
There are so many things I love about "Future Diary." The concept of time as a series of choices, each one only become true when a decision is made, is straight out of the Schrödinger's cat thought experiment and Donnie Darko. The mad god Dues makes a very short appearance, but his manipulations can be seen in almost every move. Who received what diary was a calculated choice, to bring the most entertainment to the deity whose game the diary holder's play.
A mystery series by nature, "Future Diary" also doesn't shy away from the horror or have characters look away when an axe is planted very firmly in someone's head. The character development is intriguing, as someone like Yuno can go from being the perfect, sweet girlfriend in one scene to someone you are very, very afraid of in another. The main character Yukiteru has a bit of "Shinji syndrome" (Neon Genesis Evangelion) being someone who is buffeted about by fate rather than really taking things into his own hands and being in control, but I think his potential will be reached in later volumes.
One side note: I just happened to read Volume two of "Future Diaries" and Volume two of Yotsuba&! on the same day, and it lead to some unintentional laughs. When you see the Hero of Justice's costume, you will know what I mean!