Ipung, a 13-year-old boy, is warned by his grandparents not to whistle at dusk or during the night as it's believed to be a bad omen. Instead of being compliant, he brushes it off as an outdated superstition and keeps whistling as he pleases. That night, he finds himself trapped in a nightmare, as if walking through a tunnel of terror that ends with a vision of his own death. When he wakes up, the horrors cling to him, growing stronger with every passing moment. Now, he's thrust into a deadly race against time to stop his nightmare from becoming his new reality.