Death Game! The Missing Classmate

Summary
After leaving the museum, the group is confronted by the modified souls, who tell them that one of their core group has been replaced by an imposter, and they must find out who that is before noon, or everyone in their school will be killed. As the group attempts to find the imposter, Tatsuki Arisawa, one of Ichigo's classmates, disappears. At the last minute, it is decided that the imposter was posing as Chad, but the modified souls had already kidnapped the students.