What is it about the Divergent books that makes them so popular? Is it the headlong rush to violence? One guy/gal against the system willing to brave the odds? A world gone mad? The bleakness of the landscape? Whatever it is, Veronica Roth has brought to life a landscape of fear and control and lies within lies that is at the heart of this rocket through hell very popular -- and very readable.

At the core of change there will be blood and violence. At the core of Allegiant there is also death and redemption and the people in control willing to sacrifice everything to reset the world and wipe out generations of memories and history for the sake of . . . what? Depends who you ask.

The people on the Fringe believe it is control. The people in the government outside Chicago believe it is protection of their purification project, protection of their mythology that defective genes create defective people. For the people in Chicago, it is the truth, their truth, their faction's truth. Erudite was willing to destroy Abnegation to keep the truth from the people and protect their way of life even if they had to use mind control drugs on Dauntless to accomplish their aims and wipe out what they feel is a useless faction, Candor. Everyone wants control and no one wants to listen.

Tris and Four rescue Peter, who has done so much evil for the sake of power and his own greed for violence and destruction, and take them through Amity to the outside. They leave Four's father, the leader of Abnegation behind, but that does not change Marcus's plans or his ability to get back in control. Marcus convinces Johanna Reyes, the central focus in Amity and the new leader of the Allegiant group since she decided to leave Amity to help Four and Tris against Erudite, that she needs him to gather support because his name and presence will mobilize the remnants of the factions not under Evelyn Johnson's control.

Evelyn is Four's mother, the mother he believed to be dead, and the only person to be thrown out of Abnegation at Marcus's urging. Evelyn has become the head of the factionless when she threw in with the remaining members of the Dauntless faction not under Erudite and Jeanine Matthews's control. When Erudite was put down and Tori had killed Jeanine Matthews, Evelyn took control, abolished the factions, and became dictator, forcing the factions to disband and adopt factionless ways. Everything in Chicago is upside down, but Four has betrayed his mother, rescued Peter and Tris's brother Caleb, and fled for the outside with Amity and Johanna Reyes's help.

What they find is not a world in need of their divergent to set the world to rights, but the Bureau of Genetic Welfare and another layer of truth that belies the Truth they fought so hard to reveal against incredible odds and great personal loss.

Tris, Four, their friends and enemies, Peter chief among them, try to fit into a new world without factions and focused on the goal of fixing what went wrong in a country they didn't know existed when scientists decided to fix society's evils by changing their genetic code. Chicago was one of several enclosed cities where the goal was to fix the genetic mistakes and recreate a purer genetic heritage of which the Divergent were an integral part.

Tris and Four are tested and she is still Divergent, but Four is not. He is genetically deviant and less important in the world that the head of the bureau, David, wants to reset. The landscape opens up and a very different kind of prejudice and rebellion are revealed where the genetically deviant are slaves and menial laborers with a limited ability to advance themselves and the genetically pure, like Tris, are thrust into leadership positions. Rebellion is brewing and Tris is once again at the center of a maelstrom of change and violence where she will have to decide who to sacrifice next.

As if the imploding world of the factions in Chicago was not a violent enough landscape, Veronica Roth spreads out into the rest of the post apocalyptic American landscape where the economy has been destroyed and all semblance of a working and flourishing society has crumbled. Headquartered in what once was O'Hare airport, the Bureau has created a new kind of division between the haves and have nots by pinning it all on genetics. Underlying this new tyranny the one fact that is lost in the genetic shuffle is the resilience of humanity to bloom and grow in stony ground and continue to adapt and advance. Tris and the other Divergents are, for lack of a better comparison, the latest X-Men (and women), the evolution of the human species.

Roth focuses all of her attentions on Tris and Four and their friends -- and frenemies like Peter and Caleb -- and their struggle to return their world to one they recognize, a world of factions, but with a new focus. Evelyn's focus has been tight control and resentment of those she feels tossed her and a significant portion of their society onto the rubbish heap, forcing them into servitude and starvation. It is difficult to see Evelyn fitting into Abnegation society, especially since she has none of Marcus's ability to compartmentalize and justify his brutality to her and to their son, Tobias/Four.

Tris adapts quickly, but cannot come to grips with Caleb's betrayal of her and their parents, or how she missed Caleb's lies about who and what he was. What's more devastating is how he justifies his betrayals by upholding Jeanine Matthews's version of the truth and what he did in Jeanine's service to deliver Tris to death.

Roth puts the focus on the rebellion in the Fringe, within the Bureau, and against Evelyn's tyranny and yet she still manages to open up the heart of the main characters while adding more people and to the mix, always delving deeper for hidden truths and flaying mythologies for the seeds of their beginnings. There is no lack of violence and the violence gets bigger with high tech weapons, explosives, and a death serum protecting the serum that will reset Chicago and return the experiment to a world of factions and demolished memories. Allegiant lives up to the groundwork laid by Divergent and Insurgent and imagines a new landscape with free access to the rest of the world.

Roth does an excellent job of navigating this new and broken America and wraps it all up nicely in a bow reminiscent of an original Star Trek episode where a rigidly controlled world is allowed one day of excess and chaos and the computer controlling their society destroyed. What remained was a world of problems and unleashed minds and emotions finding a way to live in a more real, and usually chaotic, world.

The Divergent world is not without its problems, and adapting to change without the rigid construct of the factions makes it difficult, but Roth leaves readers with the hope that the scars will heal, the pain will ease, and the world will keep on ticking, ticking, ticking. I give Allegiant 4/5 stars. It is an admirable attempt to join up all the loose ends and offer a mustard seed of hope, but not without some devastating destruction wrapped in a nice neat bow.