Source: Team99's youtube channel: ep.1 + ep. 2.
There will be 5 episodes in total! It was filmed a while ago already, for their 100th day since their debut and before Miss Me? promotions, so both Mina and Sejeong are there.
Different teams go through various tasks (guessing games, paraglider...) in Jeju, with a little bit of trolling from the PD team each time. The episodes should have been a little bit longer, as the editing goes from one scene to the other too fast (especially the bravery task in the "haunted place") but otherwise it's fun and you'll get a good glimpse of their personnalities!
PS: don't put it on too loud, they're the screaming type lol.
Mods, can we have a Gu9udan tag, pretty please?