Petaka Gunung Welirang follows five friends celebrating their graduation by climbing Mount Welirang, but their trip takes a very different turn when they pass through Alas Lali Jiwo and hear the sound of gamelan music coming from the forest.
And that’s where things start getting properly weird – the basic setup is pretty straightforward here, and according to the official CGV synopsis, they hear gamelan while travelling through the forest, followed by a series of mysterious events that eventually leave the group separated inside what is described as a magical dimension of terror, so this isn’t simply a case of five people getting lost on a mountain.
Trailer
Indra Gunawan Directs the Film
Petaka Gunung Welirang is directed by Indra Gunawan, with Antonio Blanco Jr and Alika Jantinia listed among the starring cast, with a reported runtime of 105 minutes – the cast information a bit limited, with Antonio Blanco Jr and Alika Jantinia being the two performers specifically listed – the film was released theatrically in Indonesia on July 2, 2026.
The Forest Is Called Alas Lali Jiwo
The big thing here is Alas Lali Jiwo, which literally translates as something along the lines of โForest of Forgotten Souls,โ, – it is associated with Mount Arjuno-Welirang, an area in East Java that has a long history of supernatural stories and beliefs surrounding the mountain and its forests.
That makes it a pretty natural location for an Indonesian horror film too, because the filmmakers don’t have to invent an entirely fictional haunted forest, so the story can take a real mountain environment and build its supernatural horror around an existing name and reputation, and then there is the gamelan.
Hearing traditional Javanese gamelan somewhere deep inside a forest while you’re hiking is exactly the sort of thing could work well in a horror film because it doesn’t immediately need to show anything – you hear something that shouldn’t really be there, and that is enough.
Indonesian Mountain Folklore Fits the Story
Mountains and forests have a particularly strong place in Indonesian supernatural storytelling, and Alas Lali Jiwo is one of those names that already carries an ominous meaning before a horror filmmaker puts a camera there, as stories surrounding sacred mountains and remote forests often involve warnings about behaviour, spirits, unseen beings and places where ordinary rules are not necessarily supposed to apply.
Petaka Gunung Welirang is taking that general cultural territory and turns it into a modern horror story about a group of young people who enter the forest while celebrating a completely ordinary milestone in their lives – the contrast is quite good – graduation celebration on one side, supernatural forest on the other.
They probably should have picked a restaurant.
Check out some more Indonesian horror movies.
Leave a Reply