Weekenders Adventures of Grandma Got Run Over by a Reindeer is the first Christmas crossover film made by Sonic876. It will appear on Google Drive as a double feature with Weekenders Adventures of The Nightmare Before Christmas on December 2017.
The show begins by introducing Jake Spankenheimer, along with his family, most notably his Grandma, who owns a small general store in the town of Cityville. The store happens to be the only piece of property not owned by Austin Bucks, the wealthiest man in town, whose CEO corporation specializes in making Christmas easier and less involved for the town's busy residents. Grandma, however, tells Austin that his method of trying to make Christmas easier is not really for the best and refuses to sell the store. This runs afoul of the gold-digging Cousin Mel, who plans to sell the store anyway.
Jake loves the holiday season, as does his grandmother, though most of his family is not as excited about it. Jake and his sister, Daphne, argue over Santa Claus' existence, as Jake's parents gently try to break the news to him that Santa is not real. Meanwhile, Cousin Mel comes up with a plan to sabotage Grandma's famous fruitcake recipe, secretly add an extra ingredient with hopes that they won't sell, forcing Grandma to sell the store to Austin. Grandma, who hasn't taken her medication that evening, then takes the fruit cake with her when she leaves the house on Christmas Eve night, but Santa and his reindeer fly overhead, suddenly out of control, crash into her. Jake witnesses the accident, but the family refuse to believe him. The next morning, however, Grandma is missing, and the police find an imprint of her in the snow, along with her belongings. Cousin Mel also finds a letter that she quickly hides from the others.
Nine months pass without Grandma and the store's business drops; during this time, Cousin Mel comes up with a new plan to sell the store to Austin, by tricking Grandpa into giving her his power of attorney. However, when Jake objects, Austin agrees to give him another week in order to find Grandma before going through with the deal. Adamant in his belief that Santa ran over her, Jake emailsSanta, and soon Quincy, Santa's head elf, comes to take Jake to the North Pole. It turns out that Santa had taken Grandma back to the North Pole for medical treatment. Unfortunately she since has amnesia, and until receiving Jake's e-mail Santa been unsure of who she was. As Jake explains the situation, Santa, Quincy and the amnesiac Grandma agree to go with him to stop the deal.
When they arrive in Cityville, however, Cousin Mel and her attorney, I.M. Slime, quickly tricked Grandma into going with them. After Santa explains to Austin what happened, Jake and Quincy discover that Grandma has gone missing again. Cousin Mel then use the opportunity to accuse Santa of being behind her disappearance, and he is put on trial for kidnapping, leaving the scene of an accident and "sleighicular negligence". The two then plot to sue him, deducing that someone who can pay for billions of presents must be incredibly wealthy.
Jake suspects that Cousin Mel may have been involved in Grandma's second disappearance, and follows her to a cabin in the woods where she and I.M. Slime are keeping Grandma out of sight. They rescue Grandma, and find Santa's letter explaining what happened that Cousin Mel had found at the site of Grandma's accident—and also the vial of the ingredient Cousin Mel added to Grandma's fruit cake that Christmas Eve night, which had the effect of "reindeer-nip" that reindeer are strongly attracted to. They then manage to restore Grandma's memory by feeding her some of her own fruit cake, and rush to the courthouse to prove that Cousin Mel has been behind everything that happened to Grandma.
Confronted with the evidence, Cousin Mel is forced to confess everything she did. She's even confess that she hates the true meaning of Christmas and how everyone share and cares. She is then placed under arrest and the judge lets Santa go. Austin approaches Grandma again, this time offering to franchise her store throughout the country, having seen how much she and Jake care about their family and business.
The show ends with Grandma accidentally picking up the tainted fruit cake instead of her own recipe, with the result that Santa hits her again as he's trying to fly back to the North Pole. Grandpa and Jake pick her up; this time Grandma didn't suffer amnesia. Santa's sleigh takes off into the night with him saying the Spanish phrase for "Merry Christmas".