Best Mystery Anime of 2003

In a world on the verge of collapse, an old legend tells that when the end arrives, the path to paradise will open. This perfect world offers the only hope for the few living things left in this desolate land, but the myth says only wolves can discover the way to this fabled place. Although they were believed to have vanished long ago, wolves still exist, hiding among humans by using complex illusions. A lone wolf named Kiba is pulled by an irresistible scent to Freeze City, a poor settlement ruled by the cruel Lord Orkham. There, Kiba finds that wolves Hige, Tsume, and Toboe have also been lured by the same smell. Chasing the fragrance of "Lunar Flowers," which are rumored to unlock the door to their perfect world, the wolves travel across barren lands and decaying cities in search of their legendary paradise. But they are not the only ones hunting for this haven, and others with darker motives will stop at nothing to get there before them.

In the subterranean city of Lux, shrouded in darkness, its inhabitants live under constant dread and subjugation by competing criminal syndicates. Cut off from the world above, these gangs interact with the surface solely through the mining of "raffia," the city's sole reason for existence. This rare mineral, found only in Lux, serves as the foundation for "texhnolyze" transplants, which allow humans to replace body parts with cybernetic limbs. These prosthetics uniquely avoid immune rejection, and the mysterious "Class" organization holds the privilege of researching them. The Class, which also oversees raffia production, entrusts its executive power to a group called Organo, led by Keigo Oonishi—a self-righteous man with texhnolyzed legs, rumored to hear the "voice of the city." The fragile power balance in Lux shatters when a mysterious newcomer, Kazuho Yoshii, begins a series of crimes that incite conflict among the gangs. Amid the ensuing chaos, new figures emerge: Ichise, a former boxer mutilated by Organo and recently fitted with texhnolyzed limbs by Eriko "Doc" Kamata; and Ran, a young florist with the ability to see the future. As Lux spirals into madness, both Ichise and Ran become entangled in the greatest crisis the city has ever faced.

Shiki Toono awakens in a hospital room possessing the ability to perceive invisible lines. These delicate threads, which compose all matter in Shingetsutan, cause an object to be instantly destroyed when cut. Shiki realizes that tracing the lines of anything leads to its imminent destruction. Keeping his supernatural sight a secret, Shiki attempts to live his second year of high school in tranquility. However, this calm is shattered when Shiki encounters a mysterious woman with striking red eyes on his way home from school. After a sudden mental breakdown, he seemingly kills the woman and then loses consciousness. As if matters couldn't worsen, Shiki is attacked the following day by a pair of demonic hounds—facing certain death, he is rescued by the timely arrival of the same woman from the previous day. She identifies herself as Arcueid Brunestud, a vampire princess. Deciding to join forces, Shiki and Arcueid set out to discover the truth about their heritage and the recent series of murders occurring in the town.

Desperate to salvage his failing writing career by collecting a hundred ghost stories, struggling author Momosuke Yamaoka travels across Edo-period Japan in search of inspiration. While exploring the mountains, he meets a monk called Mataichi. Ignoring the warning to retreat, Momosuke continues onward and witnesses Mataichi and two accomplices commit a murder. It is revealed that this trio operates as vigilantes who investigate paranormal cases, exacting final punishment on the guilty. As Momosuke keeps looking for material, he frequently encounters the three outlaws and grows more entangled in their operations. Drawn deeper into the shadows, he struggles with the ethical implications of their deeds and the blurry boundary separating humanity from the supernatural.

Loki, the trickster god of Norse mythology, has been banished to the mortal realm for what seems to have been a poorly considered prank. As part of his punishment, he is transformed into a child. He learns that the only way to return to the divine world is by collecting the dark auras that corrupt human hearts, so he opens a detective agency to accomplish this task. A human girl named Mayura, who is obsessed with solving mysteries, soon joins him and contributes in her own way. But before long, other Norse gods start appearing, and most of them are determined to kill Loki for reasons that remain unclear.

Kyuu is a typical boy with a talent for logic and reasoning. Hoping to become a detective, he learns about the Dan Detective School (DDS), a renowned institution where students are permitted to carry weapons. Alongside Megu, who possesses a photographic memory, martial arts expert Kinta, genius programmer Kazuma, and the enigmatic Ryuu, Kyuu investigates numerous meticulously planned crimes while always pursuing the truth.

Hatsuki, a high school student harboring intense romantic feelings for her sister Hatsumi, witnesses Hatsumi vanish in a flash of green light on her sixteenth birthday. Guided by a creature that looks like a plump baby chick, Hatsuki tracks her sister to the Great Library, a realm containing various worlds preserved within books. Finding Hatsumi absent, Hatsuki embarks on a journey across different books to find her beloved sister.

According to an old legend, eating mermaid flesh grants immortality. Five hundred years ago, Yuta unknowingly consumed a piece of such flesh. For centuries, he wanders Japan, hoping to find a mermaid who might restore his humanity. When he finally discovers one, he learns that she and her companions have been raising a girl as food, intending to eat her and steal her youthful appearance to stay young themselves. Yuta kills the mermaids and rescues the girl, but she has already ingested some mermaid flesh. Though he had to destroy them, Yuta is not too disheartened. His once-lonely existence is over now that he has found a companion in Mana. And Mana, who spent her entire life confined to a small hut, finds joy in even the simplest things. Together, Yuta and Mana search for more mermaids, hoping to become normal humans once again.

In Kirin Town, Ranma and his partner Rella run the R&R Detective Agency. A staged accident causes a strange condition where the two detectives swap bodies exactly at midnight, with Ranma vanishing and the beautiful Rella appearing, and vice versa. They must find out who is behind this mysterious experiment on their bodies and why, all while continuing to operate their agency.

Jack Hofner and Rowe Rikenbacker serve as the L/R duo for Cloud 7, tasked with safeguarding the Royal family of Ishtar, their precious assets, and their public image. The pair encounters one of the most challenging assignments of their professional lives when they are ordered to guard Noelle, a contender in the 15 Year Princesse competition. What initially appears to be a straightforward duty quickly escalates, drawing in the entirety of Cloud 7 as they become entangled in a complex web of intrigue featuring bombings, corruption, and murder.