Here's a Christmas-flavored adventure idea for a modern setting that contains magic.
THE ELF ON THE SHELF MASSACRES
Someone is murdering the families of witnesses against Papa Jambo, the reputedly magic-using crimelord who is currently on trial for multiple murders. Despite heavy police protection, the assassins are still managing to infiltrate the homes and murder the families in their sleep; in one case, they even killed one of the officers on the protective detail.
After these shadowy assassins kill a pair of evidence technicians at a crime scene, the player characters are called in to help the investigation. Upon inspecting the crime scenes, they find one thing in common: Each home has an Elf on the Shelf doll in it... and at one point, one of the characters is attacked by one of the toys after it animates. (Use Kobold stats, 1d4 points of damage with a knife or some other sharp household object).
With some investigation, the characters discover that the Elf on the Shelf dolls were all sent to the family from the same downtown address, even if the packages all appeared to come from a variety of hard-to-contact relatives.
Upon visiting the warehouse, the party is attacked by 24 murderous Elf on the Shelf dolls. They attack in groups of 1d6+1 until all are destroyed. Further investigation of the warehouse reveals other addresses to which killer dolls were sent that morning, as well as the following (roll 1d4):
1. That Papa Jambo's apprentice is animating the dolls and that he has moved to a different location with 48 more... which will be sent to judges and other law enforcement officials if he has the chance.
2. That one of Papa Jambo's rivals are trying to frame him for the murders--and that rival is an even stronger and more evil sorcerer than Jambo.
3. Family members or loved ones of the player characters have been targeted to recieve killer Elf on the Shelf dolls... and that they may already be in their homes!
4. The Papa Jambo on trial is a look-a-like impostor and that the real crimelord is at a secret location, plotting a monstrous revenge that will turn Christmas Eve into a bloodbath!