It's Christmas Eve and a huge blizzard has just shut down the airport; threatening to ruin holiday plans for all stranded travelers. Snowed in en route to their father's house; two Unaccompanied Minors - dubbed UMs - Spencer (Dyllan Christopher) and his little sister; Katherine (Dominique Saldana); are ushered to the airport's Unaccompanied Minors Room; a holding cell for dozens of stranded; parent-free kids from all over the country. Caught in the crossfire of projectile cupcakes and juice boxes and desperate to escape; Spencer makes a run for freedom along with four other UMs; who couldn't be more different if they tried: spoiled rich girl Grace (Gina Mantegna); trailer-park tomboy Donna (Quinn Shephard); academic overachiever Charlie (Tyler James Williams) and comic-book geek Timothy Wellington a.k.a. "Beef" (Brett Kelly). With the airport's peevish Passenger Relations Manager Oliver Porter (Lewis Black); his lackey assistant Zach Van Bourke (Wilmer Valderrama) and every airport security guard hot on their trails; this group of UMs from cliques that don't mix learn to ditch their differences and help each other flee the clutches of airport authority. Meanwhile; Katherine and the other UMs have been herded to a nearby hotel to wait out the storm. Determined to reunite with his little sister and fulfill her unspoiled vision of Santa Claus arriving on Christmas morning; Spencer enlists the help of his UM posse. Working together as an unlikely family of their own; they outwit and outrun Oliver and his crew. Plummeting through baggage chutes; rummaging around unclaimed luggage and canoeing down a snow-covered hill; they turn Christmas at the airport into holiday pandemonium and; along the way; prove that the holidays aren't about where you are; but who you're with.