The Shadow Thief is on trial for the murder of Firestorm and it's up to Kate Spencer to make sure he's found guilty but some of his friends are on the way. Meanwhile, someone's murdering past Manhunters...
The second Manhunter volume is even better than the first. Kate learns more about her costume's capabilities, tries to quit smoking, and even works on her relationship with her ex. Also, there's a lot of great action. I can't say enough good things about the Kate Spencer character. She's tough and kind of a bitch sometimes and I'm quickly becoming attached to her. It's a shame she'll probably never make another appearance post-New 52.
I think the reason this book developed a cult following is much the same as Starman. Andreyko took a concept no one had done anything interesting with in years, Manhunter, and pretty much did what he wanted to with it while still showing respect for the past. Couple that with great writing and you have a winner on your hands. Too bad people ignored this book and Gotham Central in favor of the same old bullshit when it was being produced.
That's really about all I have to say. Anything else would spoil too many plot points. Like I always say with Starman, if you're looking for a super hero book that's about more than guys punching each other, give Manhunter a try.