The 1 season of BT21 UNIVERSE was broadcast on YouTube from lundi 16 octobre 2017 to mardi 28 novembre 2017. It consists of 13 episodes, the first one is called "No title" and the last one "No title".
The 'BT21 UNIVERSE' features BTS members gathered around, using their imaginations to discuss the new characters and stories of BT21 – a new character IP created in close collaboration between LINE FRIENDS and BTS.