Meitantei Conan OVA 06: Kieta Daiya wo Oe! Conan & Heiji VS Kid!

Kogorou Mouri's office receives a threatening phone call that was never meant for him. Conan quickly realizes that the strange voice and clues point toward Osaka, where Heiji Hattori becomes involved in a case surrounding a stolen diamond worth 100 million yen.

The two young detectives race to identify the blackmailer and recover the gem, but another expert has already taken an interest: Kaitou Kid. With a criminal hiding behind the mistaken call and the phantom thief hunting the same prize, Conan and Heiji have to solve the case before Kid turns their investigation into his next performance.