Heiji always seems to find himself stumbling into cases tied to the supernatural. What Conan doesn't realize is that there's a reason for this- and that Heiji's been keeping secrets of his own from him. Upon taking notice of some odd behavior from his friend, a curious Conan investigates- only to learn some secrets are better left hidden.

They had once been bound together with chains of iron- but when something happens that threatens to shatter that bond, all of Osaka is thrown into a panic with it. With Kazuha in critical condition, and Heiji having vanished, Conan is left to unravel the mystery behind a chain of serial bombings. And when a corpse of one of the bombers turns up, things turn far more complicated.