Nagano Prefecture, Yatsugatake mountain range, Mt. Mitakara. When Yamato Kansuke of the Nagano Prefectural Police chased a "certain man" into the snowy mountains, someone's silhouette unexpectedly came into his field of view. Taking advantage of that distraction, the "certain man" that he was chasing shot a rifle bullet that scratched his left eye at the same time that an avalanche happened, roaring across the area. The avalanche swallowed him whole... 10 months later. A member of the staff of the research facilities of the Nobeyama National Observatory is attacked by someone. After hearing the news, Yamato Kansuke, who miraculously made it back from the avalanche, and Uehara Yui head to the scene. During their questioning of the staff, the huge parabola antenna of the facility activates, and Yamato's left eye, which was dead as a result of the accident, suddenly begins to ache in a fierce way... On the same day's night, a colleague of Kogoro from his MPD days, nicknamed "Wani", calls him at his Detective Office. He was investigating the accident in which Yamato was involved, the avalanche, and said that Kogoro's name was in the report of that investigation. Kogoro agrees to meet him at a later date, and Conan follows him, but when they head to the meeting site, gunfire suddenly rings out... The promise that wasn't fulfilled and the flashback lodged in the dead eye. A whiteout mystery begins in these mountains hit by a snowstorm.