In all fairness, episode six carries itself pretty well, continuing the story of Kinuko, a young girl who we already know massacred her own family (although apparently nothing can be done about this as her father was already charged for the crime) - But was that where her taste for murder ended? Thanks to a little serendipity, Aoki realises that there is more to Kinuko than just the murder of her family, and so sets out to prove her guilt in some other deaths and missing persons.

I'll be the first to admit that I've never written a screenplay in my life, so I don't want to descend into Script Writing 101 here, but it seems that both of these rather large holes could have been filled very easily indeed. In the first instance, we could have been fed some line about Kinuko's father having cleared blocked out some memories, hence Aoki not knowing if he'd abused his daughter. On the second count, we know that the dog in question was tied up and left outside the scene where the bodies were stored by Kinuko, so why not use that as a clue to go and physically search the premises rather than having it all laid on a plate via MRI? Thankfully the fact that both of these points can be explained away meant they didn't spoil the episode for me too much, but I really shouldn't have to be rewriting the story in my head so that it all fits together in a more pleasing fashion.
Despite that, I do have to give some kudos to Himitsu here for losing its earlier squeamishness and delivering a no-holds barred two-parter that didn't shy away from the blood, sex and abuse which it largely consisted of - Coupled with a strong and compelling base storyline, it was actually a very good couple of episodes indeed if you can ignore the less well-realised plot points. I really hope the series can continue in this vein from here on in, as it's exactly what I was hoping for from this show from the very start.