Nature activity: Caving
Natural disaster: While a group of hot chicks work their way through an unexplored cave system, a passage collapses behind them, trapping them with bloodthirsty subterranean humanoids, a.k.a. Crawlers.
Complex says: We are all for chicks exploring tight spaces together, but we can think of better places to do that, like, say, anywhere we can set up a tripod.