Ichi the Killer is one of Miike's most monumental films and a true landmark in his oeuvre. Its qualities are unmistakable, for me though, it's never been a top tier film. There are undeniable moments of greatness here, scenes and characters that are extremely memorable, even helped define the 00s, there's just a little too much filler for my liking.
Ichi is a pure sadist, product of a trauma that never evaporated. He's used as a formidable killing machine by his mentor, but finds his equal in Kakihara. Kakihara leads a Yakuza gang and loves torture and mutilation. He dreams of facing off against Ichi, but he's not that easy to find. Kakihara won't let anyone come between him and his dream though.
The cast is superb, but it's Tadanobu Asano who stands out as Kakihara, no doubt one of the pivotal roles in his career. The film is quite extreme, very graphic and well over-the-top, that said that it's never quite as crazy or surprising as some of Miike's other films. It also slows down too much in the middle, which hurts the overall pacing. That said, there's no way around this one if you care for Japanese cinema. Regardless of it's minor faults, this is still an insane film and a true must-see in Miike's oeuvre.