What Gintama episode is this?

I was watching an episode in Japan, and I never found out the title. Gintoki, Shinpachi, Kagura, and two others are stranded on a deserted island. There is a sequence of them finding each other doing some random cray act, then they follow the group looking dejected. They find a giant box, and gas comes out from it. Gintoki and I think a few others are rapidly aged. Any guesses?