The episode opens with team members trapped inside an A-rank Monster Stage, where previous investigators have all died. Despite attempts to send reinforcements, teleportation is one-way and the passage cannot be reopened. The group struggles to stay calm, knowing strict rules forbid breaking taboos or leaving seats during the monster's performance. Tensions rise as the lead investigator finally faces the deadly Opera Monster, demonstrating incredible skill while the others watch in silence. The episode closes with a chilling warning: once the final act ends, all guests in the hall will be killed, leaving their fate uncertain.