The Zygon Invasion is easily one of the best Twelfth Doctor stories. You’ve got Peter Capaldi’s Doctor dealing with an imminent Zygon invasion, led by the enigmatic Bonnie who’s decided to torpedo any attempts at peace with the humans after their original ceasefire fell apart. You’ve got a ton of Invasion of the Body Snatchers-style paranoia, laced with some surprisingly scalding political commentary. And you’ve got, perhaps, the best Twelfth Doctor speech of his entire run. Put simply, the original episode was a masterclass in tension, paranoia, and acting. So, any novelization of such a near-masterpiece seems doomed to pale in comparison, right? Well, sort of.

On the one hand, Peter Harness’ novelization of his original scripts is decidedly fine. A very standard Target Doctor Who novelization, faithfully adapting the episode as it aired, with a smattering of deleted scenes scattered about. But in all honesty, it’s a bit disappointing. The truncated word count robs the story of a lot of its tension. There’s just not enough breathing room here for Harness to lather in any real sense of paranoia the way the TV version does. It’s clear the book wants to be a political thriller, oozing with intrigue and mystique. But it’s just got too much to do and far too little room to do it in. It can’t quite cover everything the way it wants to. So, most of the time, it reads like a slightly rejiggered version of the original script, just with the added benefit of prose that brings you a bit further into the characters’ minds.

On the other hand, though, Harness does introduce a backstory in this novelization that wholly recontextualizes the entire story. If you found yourself confused about what, exactly, Bonnie’s plan or motivations were, The Zygon Invasion novelization finally provides an answer. And it’s a truly heartbreaking answer, too. Avoiding spoilers, it makes perfect sense and adds an extra layer of emotion to an already gut-punching story. Harness explores this backstory through flashback sequences told from Bonnie’s point-of-view, spanning from moments after her birth all the way through the exact moment that radicalized her. And it’s genuinely breathtaking stuff. It’s just a shame that so little of the book actually explores that backstory. The Zygon Invasion needed something to make it stand out as a book, and this element could’ve been it had the novelization had more room to delve into it.

As it stands, The Zygon Invasion novelization is perfectly adequate. It’s a well-written retelling of the TV story that adds a few extra details here and there but largely sticks to the script. Aside from that much-needed backstory, there’s little here that works better than the TV version. And, in all honesty, it’s hard to recommend this book to anyone over just rewatching the TV episodes. The original version is just such a better way to experience a story like this, even if there are parts of this novelization that do improve the story a bit. So ultimately, if you’re a big fan of Doctor Who, and of this story in particular, then give Harness’ novelization a read. Heck, even if you didn’t like the episode, maybe the novelization will change your mind. But if this is your first time experiencing The Zygon Invasion, it’s probably best to just stick with the TV version.

3.5 out of 5 wands.