Best Mystery Anime of 2021

Emma, Ray, and the other older children have managed to flee from the Grace Field House. Yet, with relentless demons still chasing them, their difficult fight for freedom is far from over. Even as they push into the dangerous wilderness, the children hold onto hope thanks to the books by William Minerva. Hidden within those books are coded clues about the world beyond the farm—knowledge that can help them get by with their meager supplies. But when their pursuers close in, the children soon face their most terrifying ordeal yet. In Yakusoku no Neverland 2nd Season, the children struggle to endure in a strange and merciless world, searching for a safe place they can truly call home.

The world’s greatest assassin, who devoted his life to the organization that raised him, is betrayed and killed by that very group. Haunted by lingering regrets, he meets a goddess impressed by his skills. She offers him a new life in a fantasy world of magic and steel, charging him with a crucial mission: kill the hero destined to destroy that world. Reborn as Lugh Tuatha Dé, heir to a noble family of assassins serving the Alvan Kingdom, he learns from his father techniques that differ from his earlier ruthless style. As he hones his other talents and forges new connections, Lugh remains painfully aware that his present abilities fall short. To fulfill his divine task, he must attain absolute perfection to defeat such a formidable opponent.

Born under a blue moon, Vanitas was ostracized by his own kind, leaving him filled with fear and sorrow. Legend holds that he authored the cursed "Book of Vanitas," intending to use it later to exact vengeance on all crimson moon vampires. Set in 19th century Paris, Noé Archiviste seeks this legendary book. During an airship journey, he is rescued from a vampire assault by an eccentric physician named Vanitas, who possesses the very tome Noé desires. Ironically, this self-styled vampire expert is merely human, having inherited both the name and the book from his master, the original Vanitas of lore. As strange incidents within the Charlatan's Parade unfold, the doctor’s unique power to restore sanity to vampires by reclaiming their true names becomes invaluable.

Hiroshi Odokawa is a walrus with an eccentric and straightforward demeanor who leads a seemingly ordinary existence as a taxi driver. During his shifts, he encounters a variety of distinct characters, including Taichi Kabasawa, an unemployed man desperate for internet fame; Miho Shirakawa, an enigmatic nurse; the struggling comedy pair Homo Sapiens; and Dobu, a notorious delinquent. However, Odokawa’s mundane routine is soon shattered when an investigation into a missing girl connects back to him. Consequently, he finds himself pursued by both the yakuza and a pair of dishonest police officers.

A single picture is said to hold a thousand words, but for Cheng Xiaoshi and Lu Guang, it conceals countless secrets. Operating from a modest establishment called "Time Photo Studio," the two friends offer a unique service: by utilizing their extraordinary ability to enter photographs, they dive into images brought to them by customers and fulfill their requests. Seeing through the photographer's perspective, they relive the moments surrounding the photo and work to uncover how to resolve the client's wish. However, each time they enter a photograph, they face immense danger. One misstep could change the future of the person who took the picture—and possibly trigger a cascade of other events. As the scenarios they are forced to experience within these images begin to hit close to home, they must summon all their strength to set aside their emotions and concentrate on completing the job they were hired to do.

Kohachi Inugami, a private detective who specializes in occult matters, is summoned to a remote farming village by a local innkeeper to investigate a string of strange incidents where livestock are found rotting or torn apart. At the scene, he notices a peculiar boy working in the fields. Ostracized by his peers and called "Dorotabou" because of his stench, the child is surprised that an adult would pay him any mind. Fascinated, Inugami enlists Dorotabou's help with the investigation, much to the dismay of the villagers. Through their work together, Dorotabou discovers a hidden world where Kemono—creatures that resemble beasts—live alongside humans, and this revelation gives his previously hollow life a newfound purpose.

Kimihiko Kimizuka has always believed he is a magnet for trouble, having been unintentionally dragged into countless criminal cases over the years. His life spirals into chaos when he is kidnapped by strangers and forced onto a plane that is soon hijacked. Amid this crisis, he encounters Siesta, a striking silver-haired woman who resolves the situation all on her own. Siesta introduces herself as a legendary detective and asks Kimihiko to become her sidekick. Though he initially refuses, her persistence eventually persuades him to join her, setting off on a global journey to combat various threats to humanity. But their adventure ends abruptly after three years of unpredictable and joyful experiences, when Siesta suddenly dies. Overcome with grief, Kimihiko tries to wipe all memories of her from his mind. However, as he meets new people, he realizes that the mark Siesta left on his life is far from disappearing.

A group of thirty-six students, along with their school building, is suddenly transported into a seemingly endless void. As some of them develop supernatural abilities, a growing sense of alienation fractures the group. The student council attempts to enforce order, but the students with powers push back against their rigid authority. Through this conflict, they learn that this strange dimension has its own rules, which they must follow to survive. When one student takes a leap of faith, the school shifts to another dimension. Navigating the unique obstacles and conditions of each new world, the students must uncover the truth behind the phenomenon and find a way to return home.

Great Britain is buzzing with talk of a so-called "Lord of Crime," a mastermind behind the downfall of multiple corrupt aristocrats. In reality, the Lord of Crime is not one person but a trio composed of William James Moriarty and his two brothers, Louis and Albert. Together, they aim to eradicate all that is corrupt in their current world and build a new, just society for everyone. To achieve this goal, they must commit crimes, which the brilliant detective Sherlock Holmes and his partner, John H. Watson, cannot tolerate. A dangerous game of cat and mouse unfolds between the Lord of Crime and Sherlock, each trying to outwit the other. Yet despite his talents, Sherlock remains unaware that his adversary is hiding in plain sight. Caught between both sides is a woman named Irene Adler, as beautiful as she is shrewd. No stranger to controversy, Irene has become entangled in a scandal that may be too large even for her, as the classified documents she stole could shake the very foundations of the British Empire. Can Irene be rescued, or does a deadly fate await her?

The Shadows, who appear as pitch-black figures and release soot when distressed, are a noble family dwelling in a vast mansion isolated deep within the mountains, far from other humans. When a Shadow child nears coming of age, they are given a Living Doll who serves both as their attendant and as the face they would have had if not for their dark complexion. Emilico is a cheerful, newly created Doll who serves a soft-spoken master named Kate. Despite their contrasting personalities, Emilico does everything she can to fulfill her master's needs. As she learns more about her role and duties, Emilico begins to meet other Dolls and their respective masters, gradually uncovering the purpose of her existence. "Do not fret over trivial matters," states one of the rules all Dolls must follow. But how can the ever-curious Emilico ignore the deep secrets hidden within Shadows House?

The "Otherworld" is a vast and perilous dimension hidden from ordinary people. It is home to numerous creatures that threaten anyone who dares to enter. To witness its desolate yet strangely captivating landscape, one must find portals that can appear anywhere, from hidden elevators to shrine entrances. After a harrowing encounter with a terrifying Otherworld being, Sorawo Kamikoshi debates whether to continue or give up on life. Meanwhile, Toriko Nishina searches the Otherworld for her friend Satsuki, whom she believes is lost somewhere within the realm. When the two meet, a friendship develops. To gather as much information as possible about this mysterious dimension, they travel back and forth between the real world and the Otherworld. Sorawo and Toriko's bodies gradually become influenced by the Otherworld, preparing them for the many horrors ahead as both pursue their respective goals.

Rika Furude and Satoko Houjou have been inseparable best friends their whole lives in the quiet village of Hinamizawa. Along with their other friends, they share every day together, each moment brimming with joy and laughter. But as Rika and Satoko grow older, a life-altering chance appears before both of them. Rika is set on chasing her ambitions and wants Satoko to stay with her. Though Satoko is reluctant, she agrees to follow this path alongside Rika. Yet, the fulfillment of her dream creates a divide between them. This leaves the two girls inhabiting entirely separate worlds, with Rika thriving in her new life and making fresh friends while Satoko becomes increasingly alone. Yearning for the nostalgic days back in Hinamizawa, Satoko falls into despair, wishing things could be different. At her breaking point, a run-in with a supernatural being transforms Satoko's viewpoint and reveals new insights about her closest friend Rika. This sets her on a quest to obtain the future she wants—no matter the cost.

Mayumi Doujima made a bargain with her parents: if she cannot find a star she once spotted long ago by her fourteenth birthday, she will give up her dream of becoming an astronaut. The eccentric Manabu Soutouin overhears her predicament and offers to help her search for that star with the help of Yubiwa Academy's enigmatic Pretty Boy Detective Club, whose principles are: "Be pretty, be a boy, and be a detective!" However, Mayumi is special—she can perceive things ordinary people miss. Her eyesight lets her discern the finest details, from people approaching from afar to hidden traps that would otherwise go unnoticed. As the hunt for the lost star starts to go awry, the Pretty Boy Detective Club becomes involved in something far greater than they ever expected.

While traveling along a desolate countryside road, Wei Wuxian and Lan Wangji come across a stone marker inscribed with "Yi City." Continuing their investigation into the mystery of the cursed severed arm, they venture into the abandoned city in search of further leads. With the sudden appearance of an unknown cultivator, their probe into the demonic arm leads them to uncover a plot that endangers the entire cultivation world. The situation grows more severe when they realize it involves the chief cultivator of the renowned Lanling Jin Sect—Jin Guangyao. As the pair continue to assemble the key conspiracies woven into cultivation history, their allies and acquaintances begin to question their intentions. With the world turned against him, Wei Wuxian must prove that he is not the demonic sorcerer people believe him to be, in order to regain their trust and rescue the cultivation world from the sinister evil lurking within it.

On the surface, Dr. Ramune hardly looks like a proper physician—he is blunt, impolite, and frequently puts in minimal effort. However, his true skill emerges the moment patients come to see him: he can identify and treat a wide array of bizarre, unexplainable ailments that cross his path. Whether it's a student whose fingers have transformed into chili peppers or a child whose tears are made of condiments, Ramune draws on an innate, supernatural insight to uncover the root causes of these conditions. Yet finding the right remedy for each sickness carries a significant cost—and money is no means of paying it.

To safeguard the inhabitants of Xiaoji Island and preserve their tranquil way of life, Wu Liuqi, along with his companions Dabao and Xiaofei, sets off for the Xuanwu Kingdom. Their goal is to uncover the truth behind his identity and discover a means to rescue the island. Ahead of them lie further mysteries and adventures.

In the busy streets of Shibuya, a boy named Neku Sakuraba wakes up holding two black pins that let him hear the thoughts of those around him. The pins also grant him the ability to see the "Noise," dangerous creatures that can "erase" people from existence. Realizing he is stuck inside the city limits, Neku gets a message about a mission, with a warning that failure will result in his own erasure. While defending himself from a Noise attack, Neku encounters a girl named Shiki Misaki, who asks him to form a partnership pact to fight the monsters. Shiki explains that they have become "Players" in the "Reaper's Game"—a seven-day event with a different mission each day. As Neku and Shiki struggle to survive each passing day, they meet other Players and Reapers, face stronger Noise, and uncover the hidden truth behind the game's mystery.

When Yun Arikawa and his partner Haberu Katou investigate a reportedly haunted house, they inadvertently uncover a mystery that will soon engulf the entire planet. While measuring unusual radio waves, they are contacted by Mei Kamino, a graduate student studying the same signal and utilizing equipment previously installed by their company. Following a bizarre night, Yun resumes his job at Ootaki Factory, a tech firm dedicated to building Jet Jaguar, a robot envisioned by conspiracy theorist Gorou Ootaki. However, when flying dinosaur-like creatures known as Rodan are drawn to the strange signals, Jet Jaguar appears to be the sole defense against them. As Yun and Mei probe the sudden appearance of the Rodans, more perilous monsters emerge from the sea alongside an enigmatic red dust.

Kousuke Mikado has possessed the ability to see spirits since he can remember, a fact that terrifies him deeply. He attempts to suppress this gift by wearing glasses. While working at a bookstore, he draws the attention of Rihito Hiyakawa, an eccentric medium who believes their meeting was fated. Hiyakawa’s antics drag Mikado into the paranormal world, with the medium promising to help him overcome his fears if he stays by his side. As the pair collaborate, they uncover a string of malicious curses all linked to a single individual: Erika Hiura. The mystery deepens as they try to determine her motives and her connection to both Mikado and Hiyakawa.

By 2041, World War III has decimated two-thirds of humanity, and within this new order, faith in deities or supernatural forces is dismissed as absurd. To suppress potentially seditious thoughts, the state has formed a Special Weapon Enforcement division tasked with capturing and rehabilitating those who hold such beliefs. The Kirihara brothers, Naoya and Naoto, were kept hidden by their captors for years to hide their psychic powers, with a promise of freedom once the world could accept them. Now, navigating a harsh new social landscape that rejects psychics, the brothers are forced to flee from the relentless pursuit of Enforcement agents Yuuya and Takuya Kuroki.

The notorious Arsene Lupin III leads his band of thieves to Great Britain in search of the Raven's hidden treasure. This underground organization, rumored to control the British government from the shadows, has eluded Lupin for nearly a decade. However, tracking down clues becomes difficult as he faces pursuit not only from Interpol's Inspector Kouichi Zenigata but also from MI6, Scotland Yard, and Britain's top detective, Sherlock Holmes—who seems to have a personal vendetta against the gentleman thief.

Fifth season of Oshiri Tantei.