Keith’s answer to “I'm just wondering because it's been bugging me for years. Why is it that the fourth movie book in …” > Likes and Comments

I'd have to say that Extinction is my favorite as well. Just the fact that you bridged the gap and told the events between Apocalypse and Extinction, not just jump X amount of years with no knowing of how they got to the desert like the movie did, make it my favorite.