When Ash's Pikachu freed Meloetta with Electro Ball, Giovanni was overcome by the Reveal Glass's power, causing him to send the Legendary Pokémon on a rampage to destroy the region instead. Giovanni was eventually released from its possession when Jessie, James, and Meowth pushed him out of the spell circle. After Team Rocket's subsequent retreat, Ridley used the Reveal Glass and Meloetta's song to calm down the rampaging Legendary Pokémon. Afterwards, both the Abyssal Ruins and the Reveal Glass sunk beneath the waves once again.
The Reveal Glass made its first proper appearance in Colress Machine, where it was shown to be in Colress's possession, using it to transform Thundurus and Landorus into their Therian Formes to fight Blake.
The Reveal Glass may be based on the Demon Detecting Mirror, an item in Chinese mythology that could reflect the true identity of a yaoguai.