Flamebird teams-up with the Justice Society to defeat an impostor of the Kryptonian god, Rao, while Nightwing struggles to free himself from the Phantom Zone.
The Captain Atom back-up feature by very well executed. It's part 10 of an extended serial, but I didn't feel lost, at all. James Robinson hooks us in an arresting teaser of Captain Atom melting on the first page and he pulls the more refined, classical speech off a lot more convincingly than the attempts in the main story. Also, Cafu renders the more painterly style of illustration better than what's attempted in the main story, too. His figures strike the right balance of the hard-lines and cartoonish style you want and expect from superhero art, while still giving it some more fine-arts-style flourish.
Really, the main story is just dull. The "classic speech" narration doesn't read that convincingly. Rather than getting swept up in this story, I was thinking about how this comic was taking itself too seriously. The art never really pops off the page, too, and the painterly style of coloring really makes it look more often like it's unfinished. All of this really stands out when put in comparison with the Captain Atom story.
It's both a positive and negative statement about a title when its back-up feature is better than its main feature. While the story about Nightwing, Flamebird, the JSA and Rao was honestly rather dull, the Captain Atom was really well done. I'd really prefer to read a Captain Atom solo title by Robinson and Cafu instead of this.