From the 2 part novels of the same name (Ikebukuro West Gate Park) - The series is a pure retro gem, with an incredible cast (Tomoya Nagase, Yōsuke Kubozuka, Ken Watanabe and very young Tomohisa Yamashita) on Netflix.
Fun thriller/mystery show. Good characters and feels very real. If you‘re interested in the Yakuza and enjoy convincing villains I recommend this show.