Christmas is anything but ordinary when three bickering siblings from a newly blended household cannot see eye to eye. The youngest one, while completing his annual science project, accidentally calls upon the spirit of Christmas. They wake up to find themselves having switched bodies, unable to change back until they learn to spend the holidays together as a loving family.

The winter holidays are turning out to be especially stressful for Greg Heffley this year. After accidentally damaging a snowplow while making a snowman with best friend Rowley Jefferson, Greg worries he won’t get the new video game console he so desperately wants for Christmas. To make matters worse, he gets snowed in with his family, including his grumpy older brother Rodrick and annoying younger brother Manny.

Andy is a passionate artist whose family has been building Rose Parade floats for generations. When her Dad gets sick, Andy is forced to take the helm and supervise the construction and decoration of their client’s float. And to make matters worse, she’s saddled with the extra challenge of dealing with a demanding businessman Cliff, whose company commissioned the float.

Darcy has always worked hard to prove herself and be successful on her own terms, even choosing to start her own company, rather than work with her father. Returning to her hometown for Christmas, Darcy reconnects with an old rival, restaurant owner Luke, and they are forced to plan a charity event together. As Darcy spends time with her family and Luke, she starts to realize what matters most in life and sets out to mend her relationship with her father, and possibly fall in love.