Legion

Legion by Dan Abnett is the seventh installment in the Horus Heresy series. Set on the desert planet Nurth, it follows two officers of the Imperial Army who become embroiled in the Alpha Legion's secret operations.

Dan Abnett never writes anything ordinary. Tell him he can write a book about an Imperial compliance action and he'll pit his protagonists against Chaos worshiping heathens that ride giant reptiles. Tell him he's got free reign to explain why the Alpha Legion chose to side with Horus and he'll invent a whole alien Cabal who are trying to defeat Chaos by engineering the extinction of humanity. Let him write a Heresy book at all and you'll get something like Legion: original, gripping, and containing secrets that profoundly alter the canon of the Warhammer universe.

Legion is the first (and so far, only) Heresy book to foreground the Imperial Army, the billions of fighting men and women organised into thousands of different regiments that fought alongside the Space Marine Legions in the Great Crusade. In Legion the most prominent regiment is the Geno Two-Five Chiliad, one of the hundred regiments from Old Terra allowed to continue under the Emperor's rule, and its two main characters are Chiliad hetmen (senior captains) Peto Soneka and Hurtado Bronzi, both of whom by twists of fate become covert operatives working for the Alpha Legion. Dan Abnett writes ordinary fighting men well, as testified by the immense success of his mind-blowingly fantastic 40K Imperial Guard series Gaunt's Ghosts, but in Legion he has less room to play and Soneka and Bronzi go unsupported by the plethora of minor characters that make Gaunt's Ghosts Black Library's best 40K series.

The other Imperial force focused on in Legion is Alpha Legion themselves, on Nurth to help the Imperial Army defeat the savage Nurthene. We only ever see them from an outsider's perspective, however, a deliberate approach that leaves their inner workings as inscrutable as you would expect for a legion of espionage agents. The Alpha Legion are the masters of secrets but in this book they they themselves are being manipulated, by the Cabal, Warhammer's version of the Illuminati, who have foreseen the galaxy's destruction by Chaos unless Horus wins the impending civil war. The Cabal's agent on Nurth is John Grammaticus, a universe-weary human psyker who poses as an Imperial Army intelligence agent in order to obtain the Alpha Legion's cooperation, but his mission is compromised when the real Army intelligence starts to pursue him and soon his fate becomes wound up with Soneka's. There are layers upon layers of deception and confusion within this book, and in places it becomes difficult to keep straight who everyone is suspicious of and why. The Cabal do eventually get an audience with the Alpha Legion, but only after the Nurthene commit cultural suicide with the activation of a doomsday device that brings the Imperial compliance effort to a catastrophic end.

Legion is essentially a spy vs spy tale set during the lead-up to the Heresy. The setting is interesting and the action is intense, but the plot is convoluted and hard to follow. It is a relief when everything finally comes together at the end and the Cabal reveal the future of the galaxy to the Alpha Legion, leading them to side with Horus in the imminent war while almost everyone else is killed. Legion is an intriguing and masterfully written book, but it is not vital to the plot of the overall series.