After getting lost when they decided to go off the hiking trail, Jill starts to panick when they realize they're lost, Zack starts trying to think of a way to go back.
They decided to go and keep walking, after a bit they come across a cave and begin to hear weird noises from the cave. And so as such they get curious and end up investigating whatever is inside.
As they keep walking the strange noises slowly become more louder but more clearly. After a bit more walking in the cave they notice a girl, but when they crept closer they noticed she was floating. The girl saw them and let out a terrifying scream and chased after them.
Zack and Jill booked it out of the cave and just kept running without looking back. They kept running for what may have seemed like forever, with the girl still chasing them they were scared they were going to get caught.
After they had managed to get back on the trail they noticed the screaming was gone along with the girl. They were quite exhausted from all that had happened that day and so they learned to not go off the trail again.