Luiza Sauma’s second novel puts a science-fiction spin on a well-worn narrative of early midlife crisis. Iris, a Londoner nearing 30, is wondering how much longer she can spend Thursday nights trying not to throw up on the bus home after drinking with colleagues from the branding agency where she works as a “digital innovation architect”.

There’s early fun poked at this lingo. “So many valuable learnings for us to take away and ponder,” Iris’s line manager says after a presentation on hashtags. Parsing emails about the need for “dynamic, holistic social”, Iris compares herself to a detective: “but instead of solving a murder, she was trying to work out what she did for a living”.

Low-hanging fruit this may be, but it’s plucked cleanly all the same. Sauma’s curveball comes when Iris, hungover, applies for a spot on a reality show on the recently colonised desert planet of Nyx, where there is no internet and the diet is all vegan. “No more cigarettes. No more scrolling,” runs the spiel. “Just friendship, community and genuinely interesting, useful work.”

The real interest lies in Iris’s private psychodrama

After a week-long journey “via an underwater wormhole in the Pacific”, claustrophobia grows in the sealed hub that becomes home to Iris and her fellow cast members, with a measure of tension in the question of who will be next to crack from boredom and try their luck in the unbreathable atmosphere outside.

The real interest lies in Iris’s private psychodrama. When she leaves Earth, she’s hoping that her mother, Eleanor, will ask her to stay, but Eleanor has kept her own counsel ever since her husband killed himself when Iris was five – a factor, it’s implied, in Iris’s teenage experience of suicidal depression, after she was tricked into giving a friend’s boyfriend a blowjob on camera at a party.

Sauma’s exploration of childhood tragedy doesn’t really mesh with her broader social critique. If Nyx’s missold utopia serves up a careful-what-you-wish-for rebuttal of digital luddism, with the planet’s dubious allure symbolising the disappointments of millennial womanhood, the novel ultimately seems more interested in the aftershocks of bereavement. When Iris starts up an imaginary dialogue with Eleanor, it’s a sign not only of illness but of Sauma chafing against the narrative cul-de-sac she creates by giving Iris a one-way ticket to Nyx in the first place.

It feels jumbled, and while the open-ended elasticity of the scenario ought to be a good thing, it seems accidental, not designed – a symptom of how much is left dangling in a novel that proves more tantalising than fulfilling.

• Everything You Ever Wanted by Luiza Sauma is published by Viking (£12.99). To order a copy go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99