We Shall Sing a Song into the Deep by Andrew Kelly Stewart (2021)Read about the other entries on the list.
The submarine Leviathan survived the nuclear war that scoured the surface world. In the years since then, the nuclear submarine has patrolled the seas, sheltering the faithful who labour within it. The devout who call Leviathan home know that one day the final Judgement will come, the day when they will finally use their last SLBM to redeem the sinful Topsiders.
When necessary, Leviathan recruits new choristers from Topside. Many recruits are willing. Leviathan’s most recent acquisition is not. Forcibly kidnapped for her technical skills, the latest crewmember brings unwelcome news to the faithful: They may have fundamentally misunderstood the post-war world, and their great mission may in fact be deepest folly.
--Marshal Zeringue