I loved Disney animated films when I was a child, but I saw most of them on tape. I think Aladdin was one of the few I actually saw in the theatre.
Koizumi Kajuu made his debut as a professional author with Higa, with which he won the Mephisto Prize. The Mephisto Prize is awarded to unpublished novels (and the award is publication), and if you have read a few of the prize winners, you'll know it's a pretty diverse award when it comes to plot: the winning mystery novels tend to feature very unique settings or themes, quite unlike "conventional" mystery stories. To give you an idea of how diverse the stories can be, a couple of Mephisto winners I've reviewed in the past: Mori Hiroshi (with Subete ga F ni Naru - The Perfect Insider, 1996), Inui Kurumi (1998), Takada Takafumi (with QED Hyakunin Isshu no Shu, 1998), Kuroda Kenji (2000) NiSiOiSiN (with Kubikiri Cycle, 2002), Kitayama Takekuni (with Clock Jou Satsujin Jiken, 2002), Amane Ryou (2010) and Hayasaka Yabusaka (with Marumarumarumarumarumarumarumaru Satsujin Jiken 2014). So there's science-fiction mystery (Subete ga F ni Naru), historic-literary mystery (QED Hyakunin Isshu no Shu), light novels (Kubikiri Cycle) and fantasy-like mystery (Clock Jou Satsujin Jiken), all with very original and unique background stories and settings. Koizumi Kajuu's Higa is no exception, as features one of the most original settings I've ever seen in mystery fiction.
For I for one had never before read a mystery story set in twelfth century Middle-East, with the mystic side of Islam as its theme. The theme of Ali's spiritual search is not just something that runs in the background though, and in fact, his philosophical musings are often focused more heavily on than the (impossible) murder that occurs in this story, so you wouldn't be wrong if you'd choose to describe this novel not as a mystery novel with philosophical (religious) themes, but perhaps even as a philosophical novel with a mystery theme. Either way, Ali's question-answer discussions with al-Qarani and other characters make up the bulk of this novel, though you'd be surprised how much if it does ultimately relate back to the mystery plot. The theme of the Islam is not just for show here, which makes for a very interesting novel.
The mystery part of the story has some interesting points to it, though your mileage may vary on the motive part of the crime. The "locked tent murder" is an original setting: in theory, a tent is pretty flimsy thing, but it's still "locked" because the wind screen was tied from the inside to the tent, and they had to cut the thing loose to gain entry. The who and how of this locked tent murder is ultimately fairly simple, which is partially because of the very minimalistic setting (I mean, you count the number of people there on one hand with change, and they're on a mountain top in the middle of nowhere). The question of how Ali managed to arrive at the identity of the murderer however is far more impressive: there are various minor clues found inside the tent that seperately don't seem to mean anything specific, but when taken together definitely point towards one specific type of person. The list of suspects is very, very small, so guessing who the murderer is, is incredibly easy, but the logic that actually points to this person is great, making good use of the background story and also for example incorporating details of islam rituals that have been explained in the novel. What's even better is that the logic that points to the murderer includes the reason why the tent was locked from the inside in the first place: the motive of the culprit to create this locked room tent is really unique, and probably the highlight of the novel in terms of mystery.
Higa is a very minimalistic mystery novel that has an inward focus, but it definitely does some interesting concepts by providing a locked room mystery that is deeply connected to the overall theme of the Islam. This unique theme for a mystery novel, as well as the original setting, make Higa a memorable read, even if the conclusion of the story might not be well-liked by everyone and the focus on Ali's spiritual quest might make feel things a bit dragged out. It's ultimately perhaps more focused on the philosophical side of the matter, which is something I personally have less interest in, but as an 'And now for something completely different' read once in a while, Higa is certainly nowhere near being the worst possible scenario. Worth a look if you're looking for something with an original angle.