The plot revolves around two brothers, Angus and Lewis, who, after the death of their brother, embark on a perilous journey to the antrum, a supposedly cursed cave system. Their goal is to bury their brother according to their family's centuries-old tradition.
As they venture deeper into the caves, strange and terrifying events unfold, testing their bond, courage, and sanity.
You're referring to the infamous "Antrum: The Deadliest Film Ever Made"!
Released in 2018, Antrum is a horror film directed by John Hyams and written by David Hyams. The movie claims to be based on a true story, which adds to its eerie and unsettling atmosphere.