The cast were dressed in wetsuits as they prepared for river tubing at the Kalisuci cave, which is a river cave. Shindong, who is afraid of moving water, was determined to face his fear despite the cast assuring him that it is okay to opt out of the activity. Shindong took the lead in tubing after a short discussion among the cast. They all agreed that Shindong might be afraid to have a go if he saw how the other went ahead of him. The cast fulfilled their task of taking picture in the river while forming a circle, holding hands and lying on their backs above the water. In the talking head interview, Shindong credited the mission's success to the cast members who kept encouraging him. After their activity ended, the cast were shocked that they have to climb many flight of stairs as they did not realise they went quite far downstream. Eunhyuk akin the experience as being back in the military boot camp. (Source: Wikipedia)