バルーン・タウンの殺人 (Baruun taun no satsujin, The Balloon Town Murder, 1994) by 松尾 由美 (MATSUO Yumi), is currently out of print; so while in Japan recently, I bought an electronic copy. I think it's not difficult to find second hand copies there too. I certainly saw it in more than one used bookshop. It's a series of linked science fiction detective stories, all set in the same world, a near future Japan, with recurrent characters.
The classic of science fiction detective stories is of course Isaac Asimov's The Caves of Steel (1954). Many science fiction novels are a kind of mystery, where the reader or characters are trying to understand not a crime, but a world. Combining the two allows us to explore one aspect, the society in which the story is set, while the characters pursue the answer to the other puzzle. It helps of course to have characters who themselves don't understand the rules of the society in which the crime is committed. In The Caves of Steel, there is a crime committed at the intersection of two societies, both foreign to us, investigated by an ad hoc team of two detectives, one from each society. In The Balloon Town Murder, the foreign society is a part of Tokyo reserved for pregnant women, in an age where the artificial uterus has made pregnancy unnecessary. A minority of women choose to go through with pregnancy anyway, and the city has reserved an area for them, protected from harmful environmental influences. 'Balloon Town' is the non-official, somewhat derisory, name that outsiders have given the area. This setup allows Matsuo that very old science fiction trick of looking at the familiar with a stranger's eyes.
The eyes belong to 江田茉莉奈 (ETA Marina), a Tokyo policewoman, who investigates various crimes in Balloon Town. The real answers, though, are provided by an armchair detective, who deduces the answer from the data that Eta has gathered. This is Eta's friend from university, her senior in the detective fiction club there, 暮林美央 (KUREBAYASHI Mio). Kurebayashi is one of the inhabitants of Balloon Town, in the seventh month of her pregnancy when we first meet her. She doesn't share the slightly cultish seriousness about pregnancy that the other inhabitants seem to have (from an outsider's perspective); she offers 'curiosity' as her reason for coming to Balloon Town.
The title story establishes the setting and, as we expect from a science fiction detective story, it leads us to a solution that depends on aspects of the society that we have been introduced to. The style is generally light and humorous, occasionally becoming more serious or taking the humour in a more sharp and satirical direction. Throughout the book, attitudes to pregnancy and maternity are the focus, both outside the pregnant society and within it. In the following stories, humour sometimes takes the upper hand, with absurd situations and various parodic references to detective fiction (and more rarely science fiction). The second story, バルーン・タウンの密室 ("The Balloon Town Locked Room") is a locked room mystery; but the victim is only knocked unconscious. The story plays out as a battle of deductions between Kurebayashi and a deduction program on a policeman's laptop, given the name 'Professor Dowell' by one of the characters (apparently a reference to this). The third, 亀腹同盟 (Kamebaradoumei, "The League of Turtleshell Bellied Women") is a pastiche on several Sherlock Holmes stories, and I imagine that the fourth, なぜ、助産婦に頼まなかったのか? (Naze, josanpu ni tanomanakatta no ka? "Why Didn't They Ask the Midwife?") is a reference to Agatha Christie's Why Didn't They Ask Evans? In both, the mystery starts with the dying message of the title, and Eta meets the dying man as she leaves the game centre where she has been playing virtual golf. The book ends with a very minor story, バルーン・タウンの裏窓 (Baruun taun no uramado, "Balloon Town Rear Window"), whose point of reference should be obvious; this is a later addition, a very minor story, which disturbs a little the concluding character of the previous story.