For the Emperor (novel)

Commissar Ciaphas Cain, a famed member of the Imperial Guard, and his aide-de-camp Gunner First Class Jurgen are transferred to the Valhallan 296th'301st, a composite Guard unit in transit aboard a spaceship, formed from the remnants of the Valhallan 296th and 301st Regiments after both sustained grievous losses. He is introduced to Colonel Kasteen and Major Broklaw, the highest-ranking officers from both regiments. Cain discovers that tensions between the members of the 296th'301st are rising rapidly due to clashing centuries-old traditions. The tension comes to a head when a riot breaks out in a mess hall, with multiple casualties within the 296th'301st and the ship's crew.

With some luck and wit, Cain manages to defuse the situation, placating the angered ship crew and forging new unity between the Guardsmen of the Valhallan 597th, formed from the merger of the 296th and 301st. Members of the 597th responsible for the riot are sentenced to undertake suicide missions in the future.

Some time later, the 597th are assigned to the backwater planet of Gravalax as a show of force since the planet's locals have begun to defect to the Tau, a race of expansionist aliens. At a diplomatic event organised by Planetary Governor Grice, a Tau diplomat is assassinated, causing tensions to rise. Nearly immediately after, conflict breaks out across the capital, with civilian rioters and Planetary Defence Force troops fighting against and on the side of both Imperial and Tau forces. Cain and Lord General Zyvan are able to discover the presence of a conspiracy on Gravalax to initiate conflict between the Tau and the Imperium to unknown ends. During an operation to suppress the chaos, Cain and the convicted members of the 597th are recruited by Ordo Xenos Inquisitor Amberly Vail to go on a reconnaissance mission to the underground depths of Gravalax's capital city to uncover the conspiracy, where they join forces with a Tau unit.

Underground, they encounter a Genestealer Cult, confirming Vail's suspicions. Kelp, one of the convicted Guardsmen, attempts to kill Cain, but is killed by Jurgen. Another, Trebek, is killed after being shot in the chest by Genestealer cultists. Two of the convicted, Holenbi and Velade, are separated from the rest in an intense firefight. However, Jurgen is able to kill the leader of the Genestealer cultists, the Patriarch, throwing the remaining cultists into chaos, thus giving the group the chance to escape above-ground into Grice's palace. Grice shoots and kills Sorel, the last convicted Guardsman. He reveals himself as another Genestealer cultist and the assassin of the Tau diplomat, and engages the group in combat. Vail lands the killing blow, and the group is evacuated by the 597th.

After the battle, a dazed Holenbi and Velade are retrieved by a search team with little memory of their time separated from Cain, but Cain summarily executes them both with his sidearm. He uses a knife to remove a Genestealer implant in Holenbi's body, with Vail explaining to a sickened Kasteen and Sulla that both had been infected by Genestealers, made obvious by their disappearance, disorientation and missing memory after combat against Genestealers. Kasteen orders their bodies incinerated. Cain and Vail observe Tau soldiers exhibiting the symptoms of Genestealer infection being led away.

Soon after, the Tau mysteriously leave Gravalax behind, returning Gravalax to Imperial hands. Vail and Cain discuss the incident over a meal, where they discuss the ongoing extermination of local Genestealer cults; she also reveals Jurgen's nature as a psychic blank to Cain. The two toast to their friendship, and Vail promises to keep in touch with Cain.

Critical reception was generally positive.

On the website Goodreads, the novel has an average score 4.23 out of 5, aggregated from 2041 ratings at time of writing. Reviewers on the site compared Cain to the titular Harry Flashman and Edmund Blackadder of Flashman Papers and Blackadder series respectively.[1] The novel was also reviewed favourably on Amazon, with an average review score of 4.7 out of 5. Reviewers praised the novel's humorous, light-hearted nature and a good introduction to the universe of Warhammer 40,000.[2] Similarly, it is rated 4.7 out of 5 in accordance to 28 reviews on Apple Books at time of writing.[3]