Diana's eager to get home before paranormal weirdness ruins another Christmas though Martin wouldn't mind a bit of weirdness. It looks like Java's going to be stuck alone in the empty school for Christmas when Martin and Diana get a call from their Dad. He's on an expedition to the North Pole and trapped by a blizzard so he won't be home for Christmas. Diana's sorry to hear that but gets much sorrier when Dad tells her that he and their mother think it would be best for them to stay in Torrington for Xmas (no explanation why their mother would rather spend Christmas alone rather than with Martin & Diana). Java's happy for the company but Martin and Diana are gloomy about being the only teenagers left in the school. Then M.O.M. calls to invite them to attend the Center's Christmas Party (or else) which is a welcome distraction but Martin has to do some last minute Christmas shopping. Unfortunately the presents he gets are cursed by an evil elf who was kicked out of Santa's workshop and delights in ruining Christmas for others.
Martin's gifts give the peace and quiet loving Diana huge ears that are very sensitive to noise, cause M.O.M. who hates christmas music to sing everything she says as a christmas carol, make the white christmas loving Java melt snow and fufill Billy's wish to spend more time with Martin by fusing them together. To make matters worse after distributing 100 cursed gifts (which he's almost done) the elf will disappear at midnight for 100 years making the curses irreversible. Time is running out for Martin to undo the damage he's caused before it's too late and this becomes the worst Christmas ever!