WARNING: The following contains spoilers for Season 1 of The Detective Is Already Dead, now streaming on Funimation.
The Detective Is Already Dead aka Tantei wa Mou Shindeiru (Tanmoshi) wrapped up its first season with an epic finale that concluded its main storylines but also left a lot of important questions unanswered. While the Season 1 finale ended on a cliffhanger, hinting at more stories to come in Season 2, it also didn't hint at any potential answers to some of those burning questions. Here are Tanmoshi's biggest unsolved mysteries that hopefully get some answers in Season 2.
Who Is Siesta and Where Does She Come From?
By far, the biggest mystery of Tanmoshi is its titular dead detective. Who exactly is Siesta? Does she have an actual identity apart from being a teenaged girl who also happens to be the world's greatest detective? Does she have a country of origin? Throughout Season 1, Siesta is known to operate under a codename and has a reputation for solving cases before they happen. She also appears to be a huge Sherlock Holmes fan as she sometimes makes references to Sir Arthur Conan Doyle's iconic detective and seems to be her primary influence for her own detective work. She also appears to be superhuman.
Since Episode 1, Tanmoshi protagonist Kimihiko Kimizuka notes Siesta has strength and stamina that far exceed that of a normal teenage girl. She can run at high speeds while carrying him on her shoulder and she's able to incapacitate SPES pseudo-humans with bullets made of her own blood. Once a SPES pseudo-human has been infected with her blood, they can no longer harm her. Why is that? Siesta's heart has unique abilities as well. Not only can it be easily removed from her body and transplanted into the bodies of SPES pseudo-humans with no issues, but it contains her consciousness as well. This enables her to take over bodies that contain her heart. Does this mean Siesta is herself a SPES pseudo-human?
Is Nagisa Natsunagi a SPES Pseudo-human?
Another major mystery in the first season of Tanmoshi is Nagisa Natsunagi, who is also revealed to have Dissociative Identity Disorder. Two of her alter egos are also connected to SPES: one is the 7-year-old Alicia with the other being the 17-year-old Hel. According to the villainous Hel, Alicia was one of the children SPES experimented on to the point of torture. This implies Alicia was most likely an orphan who was abducted and had her body modified.
The modifications to Alicia's body were most notably used by the Hel alter ego. Having joined SEED in his villainous quest to terraform the Earth and destroy all human life, Hel is able to paralyze their opponents with only their stare. They are also capable of removing and transplanting human hearts into their own body without requiring any surgery. After taking Siesta's heart, Hel exclaimed it was perfectly suited for their body. Does this confirm both Hel and Siesta come from the same place of origin? If so, how long before Nagisa becomes aware of her DID, the role she indirectly had in Siesta's death and that she herself has pseudo-human abilities?
Who is Charlotte Arisaka Anderson?
Just as mysterious as Siesta is Charlotte Arisaka Anderson. Despite being an American teenaged girl, she too has life experiences that far exceed her age. Charlotte is particularly noted for her military combat skills, which Siesta values. She also appears to be in love with Siesta, fondly referring to her as "Ma'am" (translated as "Mom" in the Funimation subtitles) and resents that Siesta chose Kimihiko over her. Between her and Kimihiko, she was the person most strongly impacted by Siesta's death.
How exactly did Siesta and Charlotte meet? Do they -- along with Nagisa -- also come from the same place of origin? If so, does this mean Charlotte is also an orphan with links to SPES? Given how important she was to her, were Charlotte and Siesta at one point romantically involved? Past romantic involvement just might be the significance of Charlotte's locket necklace that contains a picture of herself and Siesta.
What’s Siesta’s connection to Yui Saikawa?
Perhaps the biggest unanswered question of Season 1 is Yui Saikawa's involvement in Siesta's posthumous plan to destroy SPES. At no point is it revealed the two met or interacted in the past, though Siesta was at least aware of her while she was in London. Did Siesta actually arrange for Yui's parents to procure the Sapphire Phantasm eye for their daughter? If so, why did Siesta want to involve an innocent girl in her dangerous plans, especially if the eye is using SPES technology?
What is Fuubi-san's connection to Siesta and Charlotte?
The last major unanswered question of Tanmoshi Season 1 concerns Fuubi Kase, (referred to as "Fuubi-san"). All that's known is that she was Siesta and Kimihiko's point of contact with the Japanese police. She's also, apparently, very well acquainted with Charlotte independent of Siesta and is very resourceful. Why is Fuubi a point of contact for Siesta, Charlotte and Kimihiko? Do they all share a common goal and/or history? Is it possible Fuubi-san is also connected to SPES in some capacity?
One recurring theme throughout Season 1 of Tanmoshi is that many (if not all) of the characters are connected to SPES in some capacity. They are either direct victims, allies, or are roped into SPES's orbit through affiliation with Siesta in particular. All we know about SPES is that it is a terrorist organization founded by a sentient extraterrestrial plant known as SEED, who wants to reproduce himself on Earth by killing all human life. The organization specializes in making pseudo-humans, with at least one of the main characters (Nagisa) being confirmed as having a modified body.
For all lingering questions to be answered, Season 2 of Tanmoshi/The Detective Is Already Dead will need to spend time fleshing out the backstories of its core cast of characters and their connection to SPES.