Free! Dive to the Future - Soushun no Build-up!
English name: Free! Dive to the Future Episode 0
Genres: Comedy
Type: Special, Episodes: 1
Aired: Jun 23, 2018
Studio: Kyoto Animation, Animation Do
Source: Original
Rating: PG-13 - Teens 13 or older
Synopsis:
As they adjust to life in Tokyo, Haruka Nanase and Makoto Tachibana prepare for their university's opening ceremony. However, while running some errands, they find themselves representing Iwatobi in a regional mascot wrestling tournament. Unbeknownst to them, the rest of the Iwatobi and Samezuka swim club members are watching the event's live broadcast at a local festival.

While also adapting to the quick change of pace, Ikuya Kirishima and Hiyori Toono discuss what moving from the countryside to the city was like.

Crossing paths with old friends on the bustling streets of Tokyo, the curtain rises on a new chapter in the boys' lives.