The Forest (2016)

Sara and Jess are twins.  Sara is the good reliable one, and Jess is the troublemaker.  When Jess disappears, Sara's twin-tuition tells her that Jess is still alive.  So she travels to Japan, and learns that Jess was last seen going to Aokigahara, known as the Suicide Forest.

Sara refuses to believe that Jess would kill herself, plus her spider sense tells her that Jess is still alive.   She decides to go to the forest, even though locals warn her it is a dangerous place and if she goes, then she must not leave the path.  It is said ghosts haunt the forest and target those who are sad. Also it's easy to get lost because there's such a tangle of brush.

Stopping in to a bar for a drink, she meets Aiden, a reporter.  He is planning to go into the forest with his friend Michi, a forest guide who does sweeps for bodies.  Aiden says he'll take her along, if he can write her story.

They traipse into the woods and Michi leads them off the path to look for bodies. When they find her sisters tent, it is late in the day.  A tent in the forest casts doubt on whether the person intended to kill themselves.  Michi tells them they must go back, but Sara refuses to leave.  Aiden is torn between safety and leaving Sara alone, but stupidly decides to stay with Sara. Hilarity ensues. No wait, not hilarity, horror. Yes, pure horror because they did not heed the warning of staying on the path. Always stay on the path and always heed the warning of a stranger who says don't go into the woods. Stupid girl.