“Noumnen,” by Marina J. Lostetter (Harper Voyager)

In Marina J. Lostetter’s Noumenon (Harper Voyager), astrophysicist Reggie Straifer has discovered a strange star that holds the promise of alien life. He works tirelessly to prepare a mission that will take eons to travel to the star, knowing he’ll never get to see the fruits of his labor. However, he, and many others working on the project, send their clones to safeguard their plans; these clones are replicated over and over across centuries in space as they journey to the star. Lostetter’s book is heavy on the hard science, but it’s not overwhelming. It’s tempered by very real, sympathetic characters struggling to find meaning in themselves and in their mission. The book is organized in time-skipping vignettes from each character and various versions of their clones. The only constant is an evolving A.I. that watches over everyone, protecting humanity even from itself. Despite heavy subject matter and some complicated science, the book offers a dreamlike exploration of evolving societies and the many ways humans can control, fight and love each other.

“The Stone Sky,” by N.K. Jemisin (Orbit)

The Stone Sky (Orbit) is the finale of N.K. Jemisin’s much lauded Broken Earth trilogy, and it picks up right where the last book left off. Our reluctant heroine, Essun, is still on the search for her missing daughter in the Stillness but feels responsible for the community that she saved — yet partially destroyed — with her orogeny, the ability to harness the energy of the Earth. Meanwhile, we finally get to know our narrator, the mysterious Stone Eater Hoa and how he came to be. Essun, Hoa and Essun’s daughter, Nassun, have each been shaped in different ways by the racist caste system that rules their world, and Jemisin uses her fictional Earth to more clearly define the repercussions of slavery and genocide on not only humans, but the Earth itself. Her books have abstracted real-life race issues in a way that serves to magnify the truth. At the heart of this tale is Essun and Nassun, at opposite ends of the world and ideologies, as they work tirelessly to resolve the legacy of slavery in their world.

“A Alchemy of Masques and Mirrors,” by Curtis Craddock (Tor)

Curtis Craddock’s debut, An Alchemy of Masques and Mirrors (Tor), is a classic fantasy that leans heavily on the action and political intrigue. It follows two points of view — that of a swashbuckling musketeer past his prime and a princess of ill repute. Jean-Claude saves the princess — who is born with only one finger on one of her hands and without the powers of her birthright — from death, and as punishment is assigned to be her guard until she comes of age. The pair are thrust into a dazzling and magical mystery when the Princess Isabelle is announced the betrothed of the future king of Aragoth, a land full of mirror magic. Jean-Claude is a joy as a brash and cunning man of disrepute, but the star is Isabelle, a woman who in secret has become a stunning mathematician and scientist. Those familiar with this genre will recognize all the regular beats that come with it, but Craddock’s use of magic feels natural and not overplayed, and the love between Isabelle and her musketeer-turned-surrogate father is endearing.

Everdeen Mason reviews science fiction and fantasy every month for The Washington Post.