The second season of B: The Beginning. 
 
When Keith is abducted and a friend from Koku's past resurfaces, Killer B returns and everyone is pulled into a conspiracy involving the crown. 
 
(Source: Netflix)

In a world powered by advanced technology, crime and action unfold in the archipelagic nation of Cremona. Koku, the protagonist. Keith, the legendary investigator of the royal police force RIS. A mysterious criminal organization. A wide variety of characters race through the fortified city as it is beset by the serial killer, Killer B, and a chain of crimes. 
(Source: Netflix, edited)

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