In a dystopian world divided between ground-dwellers and skydwellers, Terra uncovers buried secrets and joins a covert resistance to overthrow the oppressive Tribunal. As she navigates treacherous waters of truth and relationships, Terra must confront ancient secrets and test familial ties to bring about change.

Reader Review Summary

"Underground" is a thrilling and immensely satisfying conclusion to the Terrestrials duology by Gretchen Powell Fox. After the cliffhanger ending of the first book "Terra," readers have been eagerly awaiting this sequel - and it does not disappoint.

One of the greatest strengths is how seamlessly the story picks up right where the previous book left off. A month after regaining her memories, Terra is more determined than ever to uncover the truth about the divide between the terrestrials and the elite skydwellers who live in floating citadels above. Her blossoming relationship with Adam adds delicious romantic tension, made even more intriguing by the secrets he keeps about his own heritage.

The worldbuilding is superb, deftly expanding on the rich dystopian society introduced in book one. Fox masterfully ratchets up the stakes when Terra's brother Mica is forcibly recruited to a skyworld military academy. This nail-biting turn of events propels the protagonists into an alliance with the Underground rebel group working to overthrow the oppressive Tribunal regime.

The breakneck pacing keeps readers furiously turning pages as ancient mysteries are peeled back and shocking revelations abound. Terra's evolution from book one continues in a highly compelling way as she matures into a powerful, defiant hero in the face of the Tribunal's tyranny. Her emotional torment over having to resist the feelings she's developing for Adam is also a highlight.

Existing fans of the first book are sure to be enthralled from start to finish. Fox's immersive storytelling, creativity in crafting this fascinatingly flawed society, and ability to juggle multiple plotlines with ease and suspense is incredibly impressive. Readers are treated to a wholly satisfying conclusion that neatly ties up loose ends while still leaving room for imagination about what lies next.

For those who love pulse-pounding YA dystopian sci-fi in the vein of The Hunger Games and Divergent, Underground is not to be missed. It's the perfect culmination to a series that has steadily built an engrossing narrative populated by rich characters you can't help but root for. Gretchen Powell Fox has wonderfully realized her ambitious vision, delivering a reading experience sure to linger long after the final page.