Book review by
Michael Berry, Common Sense Media
Deeplight Book Poster Image
Undersea fantasy delivers gallons of reading pleasure.

Parents say

age 14+
Based on 1 review

Kids say

age 14+
Based on 1 review

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A lot or a little?

The parents' guide to what's in this book.

Educational Value

Deeplight offers the chance to discuss friendship, loyalty, and the power of storytelling.

Positive Messages

Storytelling can change history. Human beings can stand up against those who are taken to be gods.

Positive Role Models & Representations

Hark has had a rough life as an orphaned scavenger, but he is still kind, compassionate, and brave. He is manipulated by his friend Jelt, who pushes him to take unreasonable risks. Jelt is sneaky, cruel, and self-centered.


There's little bloodshed before the undersea climax, where Hark and friends battle a sea monster up close. Earlier, there's a stabbing that heals quickly.

Drinking, Drugs & Smoking

What parents need to know

Parents need to know that Deeplight is a new fantasy novel by Frances Hardinge (The Lie Tree). A young scavenger in a seaside Sanctuary finds a relic that seems to be the still-beating heart of an undersea god. Until the climax, the level of violence is fairly low -- a couple of stabbings that heal quickly enough, an attack by a sea monster. There's no swearing, sexual content, or substance use.

User Reviews

  • Parents say
  • Kids say
Adult Written byRobertDudley June 9, 2020

Read Them All

Every published title by Ms. Hardinge is a must read. She won the Costa Literary Award a few years ago for ALL fiction although she had been nominated in the y... Continue reading
Teen, 16 years old Written byMakii December 23, 2020

Trippy but Fun

The book is very fun to read and keeps you on the edge of your seat, however reading it also feels like wrestling an eel. The book has a lot of body horror, as... Continue reading

What's the story?

DEEPLIGHT opens half a century after the undersea Elder Gods turned on each other to the point of extinction. Fifteen-year-old scavenger Hark is sold into indentured servitude to a mysterious scientist who studies the remnants of the beasts. He and his friend Jelt find the heart of a terrifying leviathan, and its ancient healing powers begin to change both boys. How can Hark save himself, rescue his best friend, and prevent the return of the monsters that could destroy civilization? The answer lies at the bottom of the ocean, where danger lurks and secrets are hid.

Is it any good?

The call of the ocean animates only a few fantasy novels, but this lively undersea fantasy delivers gallons of reading pleasure. In Deeplight, author Frances Hardinge builds a captivating world of maritime magic and peoples it with vivid characters who don't shy from conflict. Hardinge's earlier novel, The Lie Tree, won the Costa Book of the Year prize (for English-language writers based in Britain and Ireland), and it's easy to see why. Her prose is fluid, her ideas novel and well executed, her characters unpredictable. Readers with a taste for steampunk will especially enjoy this atmospheric sea tale with echoes of 20,000 Leagues Under the Sea and Frankenstein.


Talk to your kids about ...

  • Families can talk about how Deeplight portrays a toxic friendship. Why does Hark end up doing dangerous tasks for Jelt, even though he knows how risky they are? Have you had any experience with unhealthy friendships?

  • Why do some religions wish for the end of the world? What are the dangers of cult-like behavior?

  • Why is storytelling important? How does fiction lead to a better understanding of the world and other people?

  • Why do you think sea monster stories remain so popular? What others have your read or seen?

Book details

Our editors recommend

For kids who love fantasy

Themes & Topics

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