Connor, Colin Egglesfield, and Amanda, Meredith Monroe, are vacationing in Thailand during Songkran. Connor, who has trained in Muay Thai since childhood, takes Amanda to watch a local match, but Amanda cannot bear the brutality and heads back to their hotel alone.
On the way, she gets briefly lost in the Phang Nga market, where a man known as Mr Nice Guy Dom Haetrakul offers to guide her. He leads her down a shortcut through a deserted alley, and the disguise drops as he transforms into the vampire Niran [Dom Haetrakul], dragging her away on a motorcycle. Connor tries to追赶, but another vampire blocks him. Just as the attempt seems doomed, a bald-headed man appears and decapitates the attacking vampire. Connor pleads for help finding Amanda, but the stranger warns him to leave Thailand immediately, threatening to kill him if he follows. Reluctantly, Connor tailspins into the night and tracks the mysterious savior to Kong Sai House, the residence of Kiko, a frenzied hunter of the undead.
At Kong Sai House, the police refuse to treat Amanda’s disappearance as urgent for 48 hours, so Connor returns to search. Inside, he is ambushed by Sang, a member of the vampire faction, and escapes by leaping out a window. On the ground, vampire slayer Raines [Patrick Bauchau] insists on testing Connor’s blood to prove he isn’t infected. When Connor clears the test, he begs Raines for aid in locating Amanda, but Raines cautions him to leave Thailand as well.
Undeterred, Connor investigates further and spots a photo of Niran in front of the Techno Games Arcade near Phang Nga market, suggesting the vampire-linked arcade holds the key to Amanda’s whereabouts. He eventually discovers Amanda being held in a skeletal, blood-soaked cell, surrounded by those who have already fallen victim to the draining curse. The lovers escape, but are pursued by two jai tham on motorcycles. One rider escapes with Amanda, while the other confronts Connor and is saved by Sang, who helps them flee again on a motorcycle. In a pivotal turn, Sang embraces Connor, turning him into a vampire to give them a stronger chance to complete the ritual.
The day of the eclipse arrives. Sang’s transformation requires a final act at the exact site where the curse began 800 years earlier. The Song neng rally around the plan: Raines and his slayers will cover the overlook above the site, an active dig, to wipe out any jai tham who try to interfere. Connor, Kiko, and the rest of the Song neng work with Sang to reach the designated spot. The eclipse begins at 3:00, and they have 17 minutes to complete the ritual.
The jai tham descend on their motorcycles, and chaos erupts. Connor and Niran fall through a weak section into a pit and continue fighting below ground. Time is running out, and it becomes clear that the slayers have double-crossed them. The slayers open fire, annihilating vampires from both sides, leaving only Connor and Niran protected in their pit. Connor manages to impale Niran, but when he surfaces, he finds only corpses around him. Raines steps forward, savoring the moment and calculating the profits from the vampire heads—and the future trophies. If Sang completes the ritual and ends the curse, there will be no more vampires, which would ruin his lucrative vampire-hunting business.
Connor locates Sang as Raines raises his crossbow on her. He offers to shoot Sang to spare her, but Raines hands the bow to Connor instead. Connor aims at Sang, then abruptly redirects to Raines. He carries Sang toward the ritual site, gives her one last kiss, and as the sun reappears, Sang explodes in a blaze that also takes Raines with her, lifting the curse once and for all. With the danger ended, Connor hurries back to the jai tham’s base and rescues Amanda, bringing their harrowing Songkran ordeal to a close.
