Now, don't expect too much in the form of exposition here. The film likes to take frequent violent turns into absurdity without the slightest inkling of reason. This does, however, practically guarantee surprise.
The film picks back up with Ruka, the little girl who was narrating the beginning of the film, all grown up, sitting in a car with police lights flashing all around outside.
Ruka now works as a cop, just like her dad did. She's here because a severely deranged man has barricaded himself inside an abandoned building after butchering a woman with a chainsaw. Like I said, it's gory. While he does this, Ruka slowly pulls up her sleeve to reveal a multitude of scars.
Perhaps this juxtaposition of futility and derangement is used to show the contrast between innocent and evil. Either that, or it's just setup for some truly fucked up shit.
A team of police head up the stairs, but Ruka stays behind. The deranged man has a chainsaw, which he starts twirling around like a madman. While he's doing this, Ruka pulls out a razorblade and start gashing the living shit out of her arm.
She sure has a lot of vigor for someone apparently trying to off herself.
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