A sinister game begins when a group of classmates reunites at their high school reunion, only to uncover a time capsule containing a defaced graduation album—and soon, their peers start dying mysteriously. As two former classmates race to unravel the truth behind the deaths, their own hidden secrets threaten to expose a web of lies, turning every classmate into a suspect in a nonstop suspense-driven mystery: who is the true culprit?

Kaburagi was arrested as a suspect in a brutal murder case, but he escapes. He continues to hide and move all around Japan. During this time, he meets Sayaka, Kazuya and Mai. Detective Matanuki is on the trail to capture Kaburagi. He interrogates the people who met Kaburagi, but they all describe Kaburagi differently from each other. Kaburagi has been missing for 488 days. Who really is Kaburagi? What is his plan?