In Coralina, the CyberSquad and Digit marvel at the cybersite's colorful coral reef. Inez hopes to bring back a piece of coral as a gift for her aunt. However, she learns coral is alive, and the reef is under threat. Something is causing the ocean to become hot and murky, and it’s bleaching the coral. Can the kids find the source of the heat before it's too late? Part of the "Cyberchase" series.