The gang arrives on a new island to witness the Conway Comet. Alexa shares with them the legend of the island. Later, a mysterious woman gives them a medal as they explore the ruins. After the usual run in with Team Rocket, the gang is then attacked by Gengar and Banette. They are then chased by them and Ash drops the medal the mysterious woman gave him. The Gengar, Banette and Dusknoir eventually realize it's the Hero Conway's Medal and accept Ash and the others as friends.
They then take them to the battlefield where Hero Conway battled and show them the comet. Team Rocket then tries to take Pikachu from Ash, but the gang of Ghost Pokémon stops them with their Psychic attack. Pikachu is returned to Ash, and he, Cilan, and Iris dance below the comet with the Ghost Pokémon.
The next day, the gang discovers the Hero Conway's Medal has vanished with all of Alexa's footage, which is replaced with static. The mysterious woman's revealed to have been a friend of the Hero Conway, leading the gang to speculate about her identity.