Zenigata arrives on the ship "Machine Gun Kelly", a casino on the water owned by the mafia, because Lupin plans on stealing the casino's money. Lupin and his gang manages to break into the ship's vault but was unable to escape with the money due to Zenigata's shooting. However, there was another purpose the ship had, one that Lupin was aware of; to search for a sunken ship filled with gold. Lupin managed to steal this data while he was on the ship, however, now they have to contend with Zenigata, the mafia, and a secret organization whose base is under Alcatraz, as they attempt to uncover the secret behind the organization and the sunken treasure.

(Source: ANN)

Years after the Fourth Holy Grail War, Waver Velvet becomes the head of the Modern Magecraft Theories department at the Clock Tower, succeeding the title of Lord El-Melloi II. Waver and his apprentice Gray set out to find the truth behind a mysterious shadow that stalks them, while trouble brews among the mages of the Association. [Written by MAL Rewrite]

This episode takes place before the actual planning of the School Fair and shows how the girls spend their summer holidays.

Ura Ex, extra short anime included in Blu-ray and the DVD releases of Ao no Exorcist.