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.

Young Ari struggles to cope with the absence of her mother, leading to a friendship with a neighbor who is grieving.