For the 20th anniversary of Animorphs—the series of YA books about kids with the power to shape-change who are fighting against a secret invasion of Earth—author K. A. Applegate gave a retrospective interview to Entertainment Weekly,
revealing the vast number of influences on the series. An explicit reference, though, came in the form of a name taken from Tolkien.
In Animorphs, the Yeerks are sluglike beings that take over hosts by entering the brain through the ear. This makes them one in a long list of aliens that take over others against their will, and another in the long list of slug-shaped aliens. (I bet the Yeerks and the Goa’uld from Stargate got along great.) Applegate said, “The Yeerks were straight out of scifi standards like Invasion of the Body Snatchers and Star Trek, although the name is a wink-wink to Lord of the Rings, as the Elvish word for ‘orc’ is basically ‘yeerk’ with a different spelling.”
The Elvish word she’s referring to is “yrch,” which is actually the plural for orc. And I always assumed the “y” was pronounced as a vowel and not the consonant y-sound. But if you combined them, you would absolutely get something like “yeerk.” That’s a quality shout-out they’ve made here.
One yeerk villain wasn’t influenced by Sauron or any other Tolkien character, but by Star Wars. Said Applegate:
The [major] villain of modern times is of course Darth Vader. He was cool, mysterious, evil, but with some charm and a lot of charisma. And over time we learned something about his motives. We tried to do that with Visser Three. Emotionless, relentless killing machines are ultimately boring as villains; you want some nuance and something just a bit attractive. You want the reader to feel the seduction of evil — there’s no virtue without temptation.
And while tapping into Darth Vader makes sure Animorphs has a strong science fiction pedigree, ultimately the real model for the series wasn’t science fiction at all, but a World War II story.
“One of our models was the old TV series Combat! which followed a single squad around WWII. We wanted that same tight-knit feel, that same grunt’s-eye-view,” said Applegate.
So there you go. Put a war show, Star Wars, Star Trek, Invasion of the Bodysnatchers, and Middle-Earth in a blender, add some shape-changing and the weirdest creature you can think of (no, really: Applegate says that the Andalites were meant to be the least familiar-looking creatures they could come up with), and you have Animorphs.