The dub episode title is possibly a reference to Davy Jones' Locker, as well as the fact that Sandshrew's Poké Ball was found in a locker in the flooded school.
Mira is the second of the stat Trainers the main characters have met, the first being Cheryl. However, in the games, Mira is seen in Wayward Cave and not on the way to Hearthome City.
Ash and his friends meet Mira, who later teleports them to Hearthome City with the help of her Abra.