The world of James Bow’s Icarus Down is stunning and terrifying in concept. After decades of wandering the galaxy aboard the spaceship Icarus, the last remaining survivors of a destroyed Earth settle on a new planet, dubbing it Icarus Down. The landscape of the planet is made up of steep mountains that drop off into thick, fog-shrouded forests, which are inhabited by fearsome spider-like creatures called Ticktocks. To avoid the Ticktocks, the humans live in clifftop cities named after Roman mythological figures. Their steampunk-tinged existence includes battery-operated ornithopters – their only means of travel, exporting and importing goods, and patrolling for Ticktocks.

Bow provides readers with entirely different worldviews via the novel’s two main characters: Simon Doud, from the cliffs above, and Eliza (a.k.a. Ek-Taak-Tock-Taak), a human raised in the forest of fog by the Ticktocks.

The story unfolds in two main parts, with the first focussing on Simon. Just before Simon’s brother, Isaac, is killed and Simon is wounded in a routine ornithopter-pilot training flight between the cities of Daedalon and Iapyx, Isaac reveals he suspects that their mother was murdered. Following the accident, Simon finds himself drawn to both Rachel (Isaac’s widow), and a revolutionary group called the Grounders, who seek to uncover the truth about the Icarus and their settlement’s history.

The Grounders’ efforts are challenged by Nathanial Tal, who immediately pits himself against Simon. As an important military officer and son of the chief medical officer of the Icarus, he is a powerful (and cruel) force to be reckoned with. When Simon and Rachel begin to uncover their civilization’s true history, Nathaniel frames the Grounders for sabotage, setting off an explosion that forces Simon and Rachel into a choice between certain death in Iapyx or jumping from a cliff and leaving their lives to fate. They jump.

When Simon awakes in the fog below, his first realization is that Rachel did not survive the jump. His second is that the city of Iapyx above, home to more than 5,000 people, has just been destroyed on Nathaniel’s orders. Simon is determined get back to his clifftop home, not only to protect his people from Nathaniel, but also to reveal the murder, cruelty, and conspiracy upon which the seemingly utopian civilization of Icarus Down was built.

The second part of Bow’s tale introduces readers (and Simon) to Eliza. When she first comes upon him, Eliza – who knows nothing about the people from above other than that they murdered her entire family – is tempted to kill Simon. But realizing he is human, like her, she rescues him instead. The two then embark on a long journey of understanding – literally, as they speak different languages – and in accepting each other’s concepts of history and responsibility. Eventually, Eliza takes Simon to the Elder Mother, the last remaining Ticktock, who reveals the genocide of her people.

Nothing is simple in Icarus Down. The book is laden with environmental themes and issues relevant to contemporary society, particularly the struggle for truth and reconciliation. Relationships and characters are flawed and complex: Simon is brave and foolhardy and utterly incapable of living up to Isaac’s memory, while Eliza is a steadfast yet vulnerable female heroine. The change of pace from the clifftop city to foggy forest is jarring – but purposely so – and works beautifully, catching the reader off guard and setting them up to see Eliza’s side of the story. Gorgeous, creative, and thrilling, Icarus Down is a must-read for fans of science fiction and steampunk.