The Perfect Insider (Subete ga F ni Naru) is a high-concept mystery that follows Associate Professor Sohei Saikawa and student Moe Nishinosono as they attempt to solve an impossible locked-room murder at a secluded research facility. The series is defined by its exploration of intellectual power systems, its underdog narrative featuring students outmatched by a reclusive genius, and a total subversion of expectations regarding the solution to its central puzzle.
While widely respected by mystery enthusiasts, many fans of its philosophical depth and intricate plotting often struggle to find similar titles that match its unique atmosphere.
1. Mouryou no Hako (2008)
- Streaming: RetroCrush, Tubi
- Plot: A series of bizarre crimes involving severed limbs in boxes leads a detective and a folklorist into a dark web of experimental medicine and supernatural mystery.
- Similarities: It shares The Perfect Insider‘s heavy reliance on philosophical dialogue and an isolating, cold atmosphere created by Studio Madhouse.
- Details: 13 episodes; Studio Madhouse; MAL Rating: 7.11.
2. Kubikiri Cycle: Aoiro Savant to Zekkyou no Maou (2016)
- Streaming: Crunchyroll
- Plot: A group of geniuses invited to a remote island must find a killer among them when one guest is found decapitated in a locked room.9anime+1
- Similarities: This is the closest stylistic match, featuring an “I” narrator assistant to a female genius in an isolated, high-tech setting.imdb+1
- Details: 8 OVA episodes; Studio Shaft; MAL Rating: 7.74.
3. Babylon (2019)
- Streaming: Amazon Prime Video
- Plot: A prosecutor investigating a pharmaceutical scandal uncovers a global conspiracy centered on a woman who can manipulate anyone into suicide.
- Similarities: Like The Perfect Insider, it pivots from a standard investigation into a deep, unsettling philosophical debate about the nature of morality and the soul.
- Details: 12 episodes; Studio Revoroot; MAL Rating: 6.74.
4. Ranpo Kitan: Game of Laplace (2015)
- Streaming: Crunchyroll
- Plot: A middle school student joins a genius detective to solve grotesque murders inspired by the works of Edogawa Ranpo.
- Similarities: It employs abstract visual storytelling and focuses on a bored, highly intelligent protagonist similar to Saikawa.
- Details: 11 episodes; Studio Lerche; MAL Rating: 6.55.
5. Beautiful Bones: Sakurako’s Investigation (2015)
- Streaming: Crunchyroll, HIDIVE
- Plot: A high school boy assists Sakurako, an eccentric osteologist with a passion for bones, in solving local death mysteries.
- Similarities: The dynamic between the older, anti-social genius and her younger assistant mirrors the relationship between Saikawa and Moe.
- Details: 12 episodes; Studio TROYCA; MAL Rating: 7.42.
6. ID: INVADED (2020)
- Streaming: Crunchyroll, Hulu
- Plot: Using the “Mizuhanome” system, detectives dive into the unconscious minds of serial killers to uncover clues and solve murders.ranker+1
- Similarities: It features a complex technological “power system” and subverts expectations by blending sci-fi with traditional detective logic.
- Details: 13 episodes; Studio NAZ; MAL Rating: 7.85.
7. Rokka: Braves of the Six Flowers (2015)
- Streaming: Crunchyroll
- Plot: Seven heroes gather to save the world, but since only six are destined to exist, they realize one of them is an impostor.
- Similarities: Despite its fantasy setting, the entire second half is a tense “whodunnit” locked-room mystery where logic is the only weapon.
- Details: 12 episodes; Studio Passione; MAL Rating: 7.23.
8. Un-Go (2011)
- Streaming: Crunchyroll
- Plot: A “defeated detective” in a futuristic, post-war Japan solves cases with the help of a mysterious entity that can force people to tell the truth.
- Similarities: It explores political and social systems through a cynical, intellectual lens, much like the themes of isolation in The Perfect Insider.
- Details: 11 episodes; Studio Bones; MAL Rating: 7.31.
9. Spiral: Bond of Reasoning (2002)
- Streaming: Crunchyroll
- Plot: Ayumu Narumi must solve the “Blade Children” mystery to find his missing older brother, a world-class detective.
- Similarities: It focuses on high-stakes intellectual battles and logic puzzles where the underdog must outsmart superior opponents.
- Details: 25 episodes; Studio J.C.Staff; MAL Rating: 7.08.
10. Ghost Hound (2007)
- Streaming: HIDIVE
- Plot: Three boys with traumatic pasts discover they can project their souls into the “Unseen World” to investigate a series of strange local events.
- Similarities: It shares a slow-burn, atmospheric pace and a focus on psychology, neurological science, and philosophical existentialism.
- Details: 22 episodes; Studio Production I.G; MAL Rating: 7.48.
11. Shadows House (2021)
- Streaming: Crunchyroll
- Plot: In a mansion of faceless “Shadows” and their “Living Doll” servants, a young girl discovers the dark secrets of the hierarchy.
- Similarities: It uses a gothic setting to explore a rigged power system and features significant subversion of the characters’ perceived identities.
- Details: 25 episodes (2 seasons); Studio CloverWorks; MAL Rating: 7.72.
12. In/Spectre (Kyokou Suiri) (2020)
- Streaming: Crunchyroll
- Plot: A young woman who acts as a mediator for spirits uses logic and “constructed truths” to solve supernatural problems.
- Similarities: Like The Perfect Insider, the core of the show is the long, intellectual debate required to reach a logical conclusion.
- Details: 24 episodes (2 seasons); Studio Brain’s Base; MAL Rating: 6.91.
13. Moriarty the Patriot (2020)
- Streaming: Crunchyroll
- Plot: William James Moriarty seeks to dismantle the British class system by orchestrating “perfect” crimes that expose the corruption of the elite.
- Similarities: It highlights a genius-level strategy system and functions as an underdog story from the perspective of the “villains”.
- Details: 24 episodes; Studio Production I.G; MAL Rating: 8.12.
14. Boogiepop and Others (2019)
- Streaming: Crunchyroll
- Plot: An urban legend known as Boogiepop appears during times of crisis to fight against supernatural “enemies of the world”.
- Similarities: The non-linear narrative and heavy emphasis on abstract psychological concepts will appeal to fans of Saikawa’s philosophical musings.
- Details: 18 episodes; Studio Madhouse; MAL Rating: 7.02.
15. Gosick (2011)
- Streaming: Crunchyroll
- Plot: A Japanese student in a fictional European country meets Victorique, a brilliant but reclusive girl who solves mysteries from a library.
- Similarities: It features a “locked-room” detective structure and a strong, intellectual female lead who feels isolated from society.
- Details: 24 episodes; Studio BONES; MAL Rating: 8.04.
Why These Anime Work for Mentioned Anime Fans
Fans of The Perfect Insider are typically drawn to narratives that prioritize intellectual rigor over physical action. These selected series excel at building complex “power systems” of logic, where the primary conflict is resolved through deduction and psychological insight rather than force. They often place “underdog” protagonists—students, assistants, or disgraced investigators—against monumental puzzles or systems that seem impossible to overcome. By subverting traditional tropes of the mystery genre, these titles ensure that the viewer remains as much a participant in the investigation as the characters on screen.
