The Manhattan Projects is so full of bizarre details that I almost don't know where to start. It's an alternate version of the real Manhattan Project, but here the atomic bomb is more of a smokescreen, to detract attention from the real, and really strange, work of the project. But that's just the basic setup. The real interest is in the many strange things we find here. Like Robert Oppenheimer's twin brother murdering him, eating him, then assuming his identity. Like Einstein's monolith. Like von Braun's robotic arm.
I feel like I should have read up on the real Manhattan Project before I started reading this series. I bet I would have found even more strange divergences from our reality, and probably enjoyed the book even more. As it is, a passing knowledge of the project gave me plenty to work with, and the concepts are so interesting and executed so well that I think even somebody with very little or no background knowledge would be able to get into it.
I could describe Manhattan Projects as what would have happened if [b:The Invisibles|22347|The Invisibles, Vol. 1 Say You Want a Revolution|Grant Morrison|http://d.gr-assets.com/books/1352030626s/22347.jpg|23373] had been written by Warren Ellis after binging on the History Channel, but that's kind of a shallow way to describe the basic feel of the thing. But if that description sounds interesting to you, then this is a series to check out.