Review of The Buried Dagger by James Swallow

It's taken fifty-four books, but we're here: the threshold of Terra. Horus' forces loom on the horizon as the universe focuses on the battle that is about to unfold. The last step to that edge is The Buried Dagger by James Swallow (2019).

The Buried Dagger is comprised of two primary storylines that oscillate as the book progresses. The first is centered on the Death Guard. In the opening pages, Mortarion ravages an Imperial planet but is pulled away from the action by one of his captains with direct orders from Horus himself: time to attack Terra. Slipping occasionally into Mortarion's childhood, this storyline forms the largest proportion of the book. In the second storyline, a secret operative traverses the labyrinths beneath Terra. He is approached by Malcador the Sigillite and given a special mission. Garro and the Grey Knights pulled into the action in the aftermath, Terra may fall before Horus arrives if they don't take care of business.

If Fulgrim is the story of Fulgrim, The Thousand Sons that of Magnus, Horus Rising that of Horus, Woflbane that of Leman Rus, and so on, then The Buried Dagger is the story of Mortarion. Considering this is the fifty-fourth book of the series, a series in which Mortarion has appeared numerous times, readers already have a preconceived notion of the primarch. For me, that notion was largely villainous, almost cartoonish at times with his over the top lines and stylish appearances scythe in hand. One of the challenges of The Buried Dagger is thus making the humanity of Mortarion relevant.

The Buried Dagger adds layers to Mortarion's character that didn't previously exist. Saying he is "humanized” is a step too far, but Swallow includes excerpts of his childhood and gets into the primarch's head unlike any of the books to date with a bit of stream of consciousness. As a result, he comes across not as Pratchett's Mort (sorry, couldn't resist) rather as a semi-willing villain, a bad guy with a soft spot.  Importantly, Swallow likewise distinguishes Mortarion from Curze. With both occupying the so-called dark side, the potential for overlap was huge.  But the book ensures readers get a singular primarch. I have mixed feelings about how well all these pieces of Mortarion are brought together, but at a minimum the reader can appreciate the symbolism of saving Mortarion til the very last book in the Horus Heresy, i.e. the slaughterhouse of Terra awaits.

Another challenge of The Buried Dagger is one reminiscent of Vengeful Spirit. There is a primary storyline around which the majority of the book turns, but in order to ensure readers get a novel propoer - their 300+ pages - a secondary storyline is padded on. The Buried Dagger, with its subterranean plotting, does much the same. I'm not sure the effect is any greater.

A fair number of HH readers find The Flight of the Eisenstein to be Swallow's best work in the series. I would argue for The Buried Dagger. Getting into a main character's head forces a writer to dig in, to finds degrees of subtlety that are not necessary for a fast-paced, slap-bang action thriller—which Eisenstein is. Due to the relative lack of such action, there will be some readers who find The Buried Dagger disappointing. I understand, but at the same time appreciate Swallow finding a new gear, letting the gear hit its rhythm, and controlling its speed on through to the end. 

In my head I have likened the Horus Heresy to a rocket, the Siege of Terra the explosion. As the last novel in the Horus Heresy series, The Buried Dagger thus becomes the very tip of the warhead, the moment before it penetrates the target. And it has that curtain-closing feel. The tone of the novel rings a bell, a single, solitary note.  The pause before the next page turns on the Horus Heresy.