The Anime Lad
The advanced island nation of Cremona faces a serial killer known as Killer B and a chain of connected crimes. Keith, a renowned investigator with the royal police force, returns to the center of the case. Young Koku and a mysterious criminal organization are also moving through the city, though their places in the larger pattern remain unclear.
Super Eyepatch Fox
Enter the fortified city of Cremona. Killer B is active, more crimes follow, and the royal police need investigator Keith. Koku and a hidden organization occupy other pieces of the same crowded board. B: The Beginning opens by asking how these people and incidents connect without offering the answer ahead of the chase.
Gigguku
Cremona is already dealing with Killer B when a whole chain of crimes begins crowding the city. Then Keith, the legendary investigator, steps back into the work. I am a very easy mark for that setup. Add Koku and a mysterious organization moving somewhere in the same picture, and every introduction feels like another pin on the board.
Father's Basement
The premise introduces a serial killer, a famous detective, a young protagonist, and a mysterious organization almost at once. That is a lot of concealed connection to carry. Keith is the cleanest entry point because his job is concrete. Cremona has crimes piling up, and somebody has to establish which details deserve attention.