It was kind of refreshing to watch a 70's Hong Kong movie which wasn't a full-on fight-fest of the WHACK-WHACK-WALLOP variety. Like loads of these films, this one was set in ancient China but unlike most it has a murder/mystery plot-line. Even more improbably, it turns out that this is the work of killer butterflies, so, yes, the title is extremely accurate! Unfortunately, despite these agreeable off-kilter aspects, I found this one a bit of a yawn-fest.