Justice League: The Flashpoint Paradox

This was awesome! Some of the details in the story are different that its comic book counterpart, but overall is an amazing adaptation.

I have to recognize my opinion may be a little bias as I'm a huge DC Comics fan and the Flashpoint event was the biggest thing since 1985 in terms of continuity as it rebooted everything from a new start point for all of DC characters. It has a lot of action and most cameos of characters I've seen so far. All the battles are epic, characters are well portrayed and animation's very interesting with obvious anime influence.

A lot of fun, totally worth it and if you're new to superhero animation this is a good starting point.