Space Case, by Stuart Gibbs, first published in 2014, is the first in a science-fiction series about Moon Base Alpha. Stuart Gibbs is an award-winning young adult author with two other series: The FunJungle series and The Spy School series. In Space Case, Gibbs establishes a fictional future in which humanity has built a colony on the moon in a preliminary effort to live more permanently in space. The protagonist of the story is 12-year-old Dashiell, a resident of the moon base who embarks on an investigation after an elderly scientist dies in an apparent accident. Gibbs has received numerous accolades for Space Case, which has appeared on multiple state reading lists, placed as a finalist for the California Book Award and Mark Twain Award, and nominated for the Iowa Children’s Choice Award. These acknowledgements reflect the positive reception of the book both as a strong example of science fiction and a powerful young adult novel. While the book uses age-appropriate language and descriptions, readers should be aware that one character is murdered, and that the death of that character is a central component of the plot.

This study guide refers to the 2015 paperback edition published by Simon & Schuster Books for Young Readers.

Plot Summary

Dashiell Gibson is a 12-year-old boy whose family is among the first people to live on the moon in 2040. The NASA-built Moon Base Alpha is home to several other families as well as other key members of the lunarnaut team. Dashiell, who goes by Dash, lives with his scientist mother, engineer father, and energetic younger sister, Violet. Life on the moon has been less positive than NASA suggested it would bet: The food is mediocre at best, the base itself is small and inconveniently constructed, and there isn’t much to do. Everything changes for Dash on Lunar Day 188, when he overhears the base doctor, Dr. Holtz, talking in the bathroom at two in the morning about a dramatic, world-changing discovery.

Three hours after the conversation that Dash overheard, Dr. Holtz is found dead after making an unauthorized and unsafe solo trip out of the airlock and onto the moon’s surface. Though Moon Base Commander Nina Stack insists that it was an accident, Dash is not convinced and begins pulling together clues to figure out what really happened to Dr. Holtz. Dash attempts to talk with the other adolescent on base, Roddy, about what could have happened, but Roddy is focused on his virtual reality games.

A new launch arrives with additional lunarnauts. To keep Dash busy, Nina puts him in charge of welcoming Kira Howard, a sharp preteen who has come to the base with her inattentive father. When Dash returns to his room, Zan Perfonic, a new security worker who will be on base for just two days before returning to Earth, enlists Dashiell to covertly work toward uncovering what happened to Dr. Holtz. Dash starts by seeking Roddy’s help with hacking the base computers, only to find Roddy being bullied by the Sjoberg siblings, the two spoiled children of the wealthy first moon base tourists. Though Dash does successfully humiliate the siblings, Roddy flees, and the mess made in the process further angers Nina, who “grounds” Dash to his family residence. Kira, however, overheard Dash’s side of his conversation with Zan and convinces Dash to let her help. Kira soon reports back with the footage of Dr. Holtz’s exit onto the moon’s surface, noting that Roddy seems to have a crush on her. In the footage, Dr. Holtz looked unhappy before exiting the air lock and signed a message using his hands; per the computer’s translation, in the message, Holtz says “Earth killed me” and to find his phone.

Dash observes the behaviors of his fellow residents at their big meal with fresh food from the launch. The Sjobergs, who insisted on being served first, are disrupted when Roddy chokes on his hamburger and must be saved by the Heimlich maneuver—the offending burger chunk strikes Lars Sjoberg in the forehead, causing him to topple his family’s table. Lars, who had many suspect business dealings back on Earth, reacts with violence and anger when the cafeteria laughs afterward, demanding to be taken back to Earth. Both Nina and Chang Hi-Tech stand up to Lars.

While bearing Lars in mind as a suspect, Dash also somewhat suspects Chang, who once accused Dr. Holtz of stealing his research idea. That night, though, after a late-night exercise session, Dash witnesses Chang stand up to Lars yet again, this time on behalf of Dr. Holtz’s memory. Dash continues his investigation, informing Zan of his recent sign language discovery and latest suspects. In a mandated session with Dr. Marquez, Dash also baits the psychologist into revealing two more suspects: Sonja Sjoberg, who has a history of violence, and Garth Grisan, who NASA has apparently excused from ever attending the mandated psych evaluations.

When Dash, Kira, and Roddy realize that Daphne is the only person absent from the mandatory memorial for Dr. Holtz, they go look for her. They find her stealing information from an administrative computer, and she admits to being a corporate spy for an adventure company that wants to establish a tourism site on the moon. Daphne, relieved at having told the truth, also reveals to the trio that an additional robot was activated on the morning of Dr. Holtz’s death. Dash realizes that Holtz likely used the robot to hide his phone in the solar array on the moon’s surface.

Kira insists they should find the phone by sneaking onto the lunar surface that night. Dash tries to find Zan in advance and enlist her help, but she seems to warn him away any time he tries to speak with her in public. Late that night, Kira and Dash carefully suit up and exit the airlock. Initially, bounding about on the moon is exhilarating, and after some searching, they dig up Dr. Holtz’s phone from near a specific solar array. However, just as they find it, a remote-controlled robotic arm attacks them from overhead.

The arm sends Dash flying, and in his fall, he cracks his helmet. Thinking quickly, Dash outsmarts whoever is operating the robot by lying about his location and staying still. He grabs the phone again, which he dropped, evades the arm, and makes it back inside with Kira right before his helmet shatters completely. Their escape and re-entry triggers the alarm, summoning all the residents of the base.

Though the phone is broken, Chang Hi-Tech quickly repairs some of the audio captured on it. The Howards, Gibbs, Nina, and Chang hear Dr. Holtz on the phone with an unknown second person who threatens to kill Dr. Holtz’s daughter if the doctor reveals his discovery: an intelligent alien life form. When the computer makes yet another error, interpreting Chang’s next request incorrectly, Dash realizes who the second person is. Pulling up the footage of Dr. Holtz on his watch, Dash has his mother confirm that what Dr. Holtz spelled in sign language was not “Earth” but the name Garth, as in Garth Grisan.

Garth retaliates by threatening to depressurize the moon base, insisting that humanity cannot learn yet that aliens exist. After a long argument, Chang subdues Garth, and Nina places him under arrest. With the murder solved, Dash works out one final mystery. He finds Zan, and she reveals her identity as an alien from a planet 10 light years away who can think herself present on the base. Her species, she explains, has been monitoring humans for some time. Now that humans are beginning to colonize space, they want to establish a relationship. Zan suspects humanity as a whole is indeed not ready, but she asks if Dash would like to be her contact. Dash agrees, even though it needs to be kept secret, and asks Zan to teach him how to project himself via thought too.