Setting: Modern day. A small town in Pennsylvania and the ice cap of Greenland.
In a flashback, the Patterson family—lieutenant Harry Patterson, mother Carol, Kami the high school valedictorian, and autistic 7-year-old Ben—are enjoying a festive evening at the Hampton Hill Tree Lighting Festival (“The Perfect Christmas”). As the scene dissolves into the present year’s festival, Harry, Ben and Kami light a candle in remembrance of Carol’s passing. After an extended furlough to help Ben stabilize, Harry is deployed on a top-secret mission just weeks before Christmas. Kami reluctantly agrees to finish her fall semester early to take care of Ben (“Let’s Fly”). Before leaving, Harry reassures Ben with a special compass (“Your True North”). Harry arrives on the ice cap of Greenland with orders to restore power to a secret military base (“Rest Up Ye Merry Gentlemen”). Not knowing the location or length of Harry’s deployment, Ben begins to shut down and tears down the Christmas decorations (“Tell Me”). He seeks comfort by imagining his mother’s presence (“Born to Believe”). On the ice cap, Harry unknowingly stumbles upon the North Pole. He is quickly sent away by disguised elves Snicker and Charley who are determined to keep his visit a secret (“In the Dark”). Regressing, Ben becomes nonverbal, and Kami worries of her ability to meet Ben’s growing needs (“Say Something”). Convinced that his father must be home for Christmas, Ben writes a letter to Santa asking for Harry to meet him at High Falls Bluff on Christmas Eve (“Jolly Old Saint Nicholas”). Amidst the harsh elements of Greenland, Harry imagines Ben calling to him (“Come Find Me”). Harry awakens in North Pole Central Intelligence and is made privy to his unusual location by Snicker and Charley (“The Best Kept Secret That Everybody Knows”). As Christmas Eve arrives, Ben sets out for High Falls, confident that his request will be granted. (“Make It Happen”).
While checking Santa letters (“Kids These Days”), Snicker and Skittle discover Ben’s letter. Meanwhile, Kami discovers Ben has left home and searches for clues to his whereabouts (“If I Were Ben”). Finding scraps of his letter, she heads out to find him. Held by NPCI, Harry grieves over his misfortunes and while searching for Ben, Kami is flooded with memories of her mother (“Never Ending Road”). Snicker gives Harry news of the letter and offers to sneak him home in the sleigh, but a reindeer grooming has rendered it grounded. They discover a mysterious compass in Harry’s pocket with sufficient magic to power the sleigh (“The Day We Hijacked Santa’s Sleigh”). In the forest, Ben enjoys his independence (“Sensational”), but as the trail gets increasingly difficult, he loses his compass and crawls into a cave. Kami finds Ben and they set out for High Falls together. Harry heads out upon arriving at the foot of High Falls, but without a source of energy, Snicker is uncertain of how to return the sleigh (“The Day We Hijacked Santa’s Sleigh Reprise”). Harry reaches High Falls and finds Ben and Kami watching the Northern Lights. Surprised at Ben’s self-sufficiency, Harry and Kami both find a renewed sense of family and hope. Inspired by Ben’s unwavering hope, they officially start the holiday season (“The Perfect Christmas Reprise”).