In the first part of the story arc, After undergoing an emergency landing, Geiz and Tsukuyomi meet Momotaros, Urataros, Kintaros, and Ryutaros in a crashed DenLiner, which was hijacked by Another Den-O in 2017.
The Kamen Rider Den-O Arc will cover episodes 39 and 40 of the TV series and will air on June 9th and June 23rd respectively.