I’ll keep this review short, since Spiral is that particularly pernicious kind of bad: the kind of bad that doesn’t distinguish itself at all. Spiral is supposed to be a mystery series. The first oh, five or so episodes have short episodic mysteries. They’re not particularly great, but they’re still mysteries nonetheless so there’s a sense of enjoyment when they’re solved. That is also apparently where the anime diverges from the manga. At this point, it just throws stuff at the wall and doesn’t try to make any sense. Not in the way that say, Lost doesn’t try to make any sense. Rather, it doesn’t even invite you to even delude yourself that any of this matters in some way, making the entire experience utterly forgetful.
Would I watch it even if I weren’t forced? Just watch Higurashi if you want some murder mysteries.