This volume wraps up Mark Waid and Bryan Hitch's brief and troubled run on the series with a bang with Terror Incognita, which sees the return of the dreaded White Martians.

The White Martians were the very first foes the current incarnation of JLA faced when Grant Morrison relaunched the book (as seen in New World Order). At the end of JLA # 4, the White Martians were defeated and were brainwashed by the Martian Manhunter into believing they are just ordinary human beings and they went on to live a normal and mundane existence, albeit under the supervisory eye of the JLA.

When the White Martians somehow regained memories of their true identity, they hatched a clandestine plan to slowly take out the members of the JLA while prepping the Earth for subjugation. The Martian Manhunter is the first casualty when he is psychically ambushed by a group of them, while Superman's secret identity is almost revealed by Lois Lane in the Daily Planet office. Batman investigates the case of psychics encountering supernatural phenomena with Nightwing, while Wonder Woman, Plastic Man, Flash, and Green Lantern struggle to protect the citizens of Murmansk, Russia from a nuclear meltdown.

While the individual members of the JLA were successful in resolving these minor crises, they begin to suspect something is amiss when Superman discovers that the very air is being changed on a molecular level, the team in Murmansk encountering three White Martians there, and Batman discovers the whereabouts of the missing Martian Manhunter in Phoenix, Arizona. Here, Batman makes a failed attempt to rescue the Martian Manhunter but is able to discover parts of the White Martians' plans and warns the JLA of their return.

Unfortunately it is all too late as the world begins to suffer from the effects of the change in the air where the oxygen molecules are broken down and replaced with an inflammable compound, disabling man's ability to create fire, the White Martians' sole weakness. With thousands of White Martians free, each one of them capable of changing their physical appearance, flight, super strength, invisibility, telepathy, and heat vision, the JLA is easily defeated and is exiled in the Phantom Zone. With the JLA missing, the rest of the heroes of Earth such as the Titans, Young Justice, JSA, and the Outsiders are easily defeated.

Very often with stories of such high stakes and epic scale, the writers write themselves into a quandary as they are unable to reasonably and logically resolve the crisis without a clichéd deus ex machina conclusion. Fortunately, Mark Waid brings the story to a very exciting conclusion as the JLA escapes from the Phantom Zone and hatches a plan that has to be seen to believe, with the Martian Manhunter facing off against Protex, the leader of the White Martians in a raging inferno.

Bryan Hitch supplied the artwork only for the first chapter, with the subsequent three chapters illustrated by Mike S. Miller, who has shown that he is more than capable of handling the so-called "widescreen" action as well as Hitch. It's a shame Miller was only the regular fill-in artist on JLA, as he certainly has the chops to handle the title on a monthly basis with his detailed and crisp style.

Chuck Dixon and Scott Beatty are the writers for a fill-in issue that was part of the Joker: Last Laugh crossover, which sees the JLA fighting a jokerized version of Doctor Polaris in Antarctica. Mark Waid returns for one last issue that is a throwback to the old Silver Age JLA stories, where Plastic Man relates the tale of how Santa Clause became an honorary member of the JLA. It's cute if somewhat inconsequential, but is terribly let down by Cliff Rathburn's pencils, which is a disappointing affair to say the least with the members of the JLA looking like badly sculpted HeroClix figures and Santa Claus resembling a drunken hobo. Still, JLA: Terror Incognita is worth picking just for the first four chapters alone, although the last two chapter should have been excised in favour of a lower cover price.