Thirteen girls are enrolled at Myoujou Academy's Black Class, but twelve of them are assassins trying to kill the thirteenth girl, with a reward: anything they want. This is the premise of Akuma no Riddle, a show that will most certainly take its viewers for a ride...
The soundtrack of Akuma no Riddle is wonderful. Fantastic. The instrumental portions have a wonderful effect on the mood, adding an eerie, disturbing feel to the show, and also manage to add excitement to the fight scenes. The opening theme is also wonderful, but the best part of the soundtrack is the ending(s). Each episode has a different ending focusing on one of the girls of the class that is sung by the subject's voice actor.
If there is one thing that can be said for sure, it is that Akuma no Riddle maintains a large amount of suspense throughout the series. In fact, this is probably what drives viewers all the way through the end. Intense moments, aided by the soundtrack, really can draw viewers in at times.
Akuma no Riddle is a death game anime. All of the characters' motives are explored, and none are left without their moment of focus.
However, one of the rules to the assassination is that it must be done AFTER submitting an advance notice, and that leads to a villain of the week type scenario. With only twelve episodes, with characters often only getting one episode of focus, almost every single member of the Black Class is left underdeveloped.
Each of the assassins has a backstory, which often reveal the motives of each assassin for participating in the Black Class. However, several of the backstories make NO SENSE or at least have minor holes in them. (minor spoilers here) One of the assassins is basically a cyborg, another is stuck as a teen for all eternity, and so on. (/spoilers) Some have more realistic and interesting stories, and their motives lend emotional support to the show's action.
In a show that features an almost entirely female cast that is centered around the development of feelings one female has for another, fan service is expected. Unsurprisingly, there are moments where the show falls into this trap. Truthfully, I was positively surprised by how minimal it was though, all things considered. Most of the time.
Akuma no Riddle is animated by Diomedea, a studio that I personally have never heard of. The animation stutters along, and anything with multiple moving parts is very sloppily done.
For a show that has the world 'riddle' in its name, one might think that riddles might play some importance, and the show tries. Each episode is named after a riddle sent to Tokaku by Kaiba, who is a poorly thought out framing device- I mean psychology teacher.
The riddles could have been used to add depth to the plot, but their attempt to deepen Tokaku's character falls flat.
Tokaku and Haru repeatedly survive by the skin of their teeth. Oftentimes, this is achieved with lucky or absurd methods, from dodging bullets to finding a key in a watermelon. The ridiculousness of this can be extremely irritating to the viewer.
WARNING MAJOR SPOILERS
No one dies. Seriously. This is a death game, and no one dies. Several of the characters are obviously supposed to be dead, and the show doesn't even really bother to explain why they survived.
This basically destroys any point the events of Akuma no Riddle had. The climax of the final episode was where Tokaku, feeling betrayed by Haru (who supposedly had controlled her using an innate ability called Primer), stabs her in the chest, then cries while holding her dead body. Haru ends up living, and thus the climax seems a bit pointless.
Non spoiler summary of the ending: The events of the show have almost no consequences.
Akuma no Riddle is a death game anime that is what it advertises, but is far inferior to shows with similar concepts. If you are looking for something similar yet better, try Mirai Nikki.