Ernest accidentally unleashes an ugly troll that plots to transform children into wooden dolls in the town of Briarville, Missouri.
Life could be pretty if there wasn't someone like Ernest P. Worrell on this planet. In this movie he helps to escape an evil troll out of his grave. That's the start of the end for the world. But... Ernest wouldn't be Ernest if he wasn't planning on saving all the people. This action doesn't make it any better. It's getting worse.—Evert Poppen
When Ernest helps two 10-year-old kids with their "Haunted House of Horror", he ends up running for his life when he unleashes an evil troll from deep below the ground. Now Ernest plots scheme after scheme to try and defeat the troll before it's too late!—loopy plane
In briarville, missori an ancient evil buried by his ancestors gets released accidentally while helping 3 kids construct the perfect haunted house now the ridiculous humorous idiot known as Ernest p worroll seeks help from the scariest woman in town to stop the troll and his plans to reconstruct his army by turning the kids of the town into little wooden dolls it's up to Ernest to finish what his ancestors couldn't and that's defeat the evil of the troll forever—Mike Garrett
Trantor (Jonas Moscartolo) is a demonic troll who transforms children into wooden dolls to feast upon their energy out on Briarville, Missouri in the late 19th Century. He is captured by townsfolk and sealed under an oak tree. One of the village elders, Phineas Worrell (Jim Varney), an ancestor of Ernest, establishes the seal under the condition that Trantor can only be released on the night before Halloween and by the hands of a Worrell - and that every generation of Worrells would get "dumber and dumber and dumber", culminating in Ernest P. Worrell.
Two hundred years later, Ernest, a sanitation worker, helps a few of his middle school friends, Kenny Binder (Austin Nagler), Elizabeth (Shay Astar) and Joey (Alec Klapper), construct a tree house in the same tree that unknowingly contains the dormant creature, after the mayor's sons demolished their own cardboard haunted house. When Old Lady Hackmore (Eartha Kitt) discovers this she angrily leaves. When Ernest follows her, he learns the story of Trantor and reports it to the kids. Inadvertently, Ernest releases the troll. Joey is walking home from the tree house when he hears something rustling through the trees Joey slowly walks and slips down in a muddy hole. Trantor grabs Joey's wrist and turns him into a wooden doll.
Ernest finds Sheriff Binder, who is Kenny's dad, and explains the situation but they do not believe him. After none of the towns folk will assist Ernest because they care about the Halloween party, he mounts a one-man (and one-dog) defense operation in preparation for Trantor's appearance. Meanwhile, Trantor captures a boy on a skateboard for his second victim.
Two local men, Tom (John Cadenhead) and the taciturn Bobby Tulip (Bill Byrge), hoping to take advantage of Ernest, sell him a variety of fake troll traps, but one backfires on the mayor's sons and Ernest is fired from his job.
Ernest, Kenny and Elizabeth return to Hackmore, where they learn that "the heart of a child, and a mother's care" are the only defenses against the troll. Later that night, Trantor claims Elizabeth as his third victim, Elizabeth is slowly walking through the woods when a plant vein slowly wraps around her foot Elizabeth runs to the tree house and climbs the ladder when Elizabeth reaches the top Trantor grabs Elizabeth's ankle tripping her and starts pulling her back. Elizabeth claws at the floor and trying to get Trantor to let go but is turned into a wooden doll.
Kenny and a friend named Gregg (Steven Moriyon) are walking when Trantor uses Elizabeth's voice to lure Kenny away, then takes Gregg as a fourth victim. Despite parents being upset at their missing children, Mayor Murdock and Sheriff Cliff Binder still proceed with a Halloween party at the school and they believe the missing children will be at the party. Trantor appears there and takes the mayor's oldest son as his fifth and final wooden doll. In the ensuing fight between Trantor and Ernest, Trantor turns Ernest's dog Rimshot into a wooden doll before being driven off by soft serve ice cream covering Ernest's hands. Kenny realizes that "mother's care" refers to milk and rallies a troll-fighting team to destroy them.
Back at the tree house, Trantor successfully summons dozens of trolls while Ernest tries but fails to stop them. The townspeople show up; however, the trolls overwhelm and beat them up. Kenny and his friends arrive and begin destroying the trolls with milk. During the fight Trantor escapes beneath the tree where he summons evil powers making him invincible, especially to milk. Kenny unsuccessfully tries to destroy Trantor, who turns Kenny into a doll as well. With the rest of the townsfolk now backing him up and telling him to douse Trantor in milk, Ernest realizes that the troll children were susceptible to the milk, while Trantor himself would be weak against unconditional love: "the heart of a child." He takes Trantor and dances with him while the mob watches, filling him with as much love as possible and finishing it off with a kiss to his snot-ridden nose, which causes Trantor to explode.
With Trantor's destruction, Ernest is proclaimed a hero. All of the wooden dolls are restored, including those from the 19th century, and life returns to normal. Sheriff Cliff Binder apologizes to his son for not believing him and Ernest. Ernest is happy that his dog is back to normal.
