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.