In a shopping mall at the peak of the holiday season, a cheerful elf takes a picture of Glen Beckett, a good looking mall Santa posing with a kid sitting on his lap. The boy points out a note addressed to Santa in the "mailbox". Glen reads it, covering his anxiety. That night, Glen is in his apartment. He's still wearing his Santa Suit but he is nervous, sweating, and loading a gun. A knock at the door startles him. After he goes to answer it, he disappears.
The agents arrive on the scene and find the note--a death threat. The note, coupled with large amounts of cash in Glen's account leads them to suspect Glen may have been using his mall Santa job as a cover for something nefarious. The investigation takes a sharp turn when they find that Glen is not an average college student making some extra money over Christmas break. He is actually a math genius and former child prodigy who spent the last ten years thriving in the University system, until he inexplicably dropped out two months ago. As the team questions Dr. Neil, Glen's trusted mentor, a portrait emerges of a brilliant but emotionally immature young man ill-equipped to deal with the world outside of academia. Glen wanted to leave the tutelage of Dr. Neil when he lost faith in what he was doing, and Dr. Neil tried hard to change his mind.
Meanwhile, Glen has come up with a program that he believes will correct some of the damage his work with Dr. Neil has done. The new program will help people, and Glen holds a gun on the CEO of a corporation to try and convince the man to look at it. Eventually, Glen turns himself in, but the CEO is so impressed with the program that he drops all charges.