Alternating between droll, chaotically hilarious, and zany in a way I haven't seen outside a children's book for a while, this book had me either thinking or cackling (I'm not exaggerating) for the entire time I read it. This is one of my favorite genres of nonfiction (now I'm second guessing that classification...hmm), and about ⅔ of the chapters made me think "huh. I'd like to see a short story about that!" It also delights me to no end that Randall Munroe and Tracy V. Wilson are friends.

I've been a fan of xkcd for coming up on two decades now, of the concept of What-If for about one decade, and of his books since 2014. Munroe's first What If? book was an absolute joy to read and I've reread it several times since its release. Both books could easily be subtitled "destroying the universe in chunks of various size for fun and legit," which is undoubtedly a feature, not a bug.

This book, in the tradition of all good sequels, stays faithful to the premise while exploring new ground. I can't wait for What If? 3.