The movie kicks off with Angela and Brian from The Office trying to convince us that they can play other characters. We're at the Holly Hills Post Office, where every year, Brian and the other postal workers judge the best Christmas card. The winner goes on the Wall of Fame. It’s Settie’s dream to win, but the same person has won 18 years in a row.

Cut to a year later, and Settie sits down to write her annual newsletter. To her surprise, it doesn’t just write itself. She thinks, "If only I had this famous author to write my Christmas card!" This author, Juan, wrote her current favorite book. So, she decides to go for it and emails Juan’s manager, offering to pay him to come to her town and write the letter for her. Juan, who's in a bit of a funk, agrees to take the gig.

When he arrives, he gets into a rideshare with Settie’s daughter, Lilly. When Settie’s rival, Sue, shows up, they lie and tell her that Lilly and Juan are engaged. Juan agrees to stay, though he’s completely confused about what’s going on. But after meeting Sue, he realizes he can’t stand her and decides to stay for a while longer.

Soon enough, sparks begin to fly between Lilly and Juan for real. But Juan is still struggling with writer’s block, even when it comes to the Christmas card. Meanwhile, Sue has been running things in town for too long—she even has rules about how people can decorate for Christmas. So, to surprise Settie, Lilly and Juan stay up all night decorating Sue’s yard with Christmas lights and lawn ornaments. They love the result.

But the night isn’t over. Lilly and Juan run lines for a play she’s auditioning for, and they share a kiss—purely for the love of the art, of course.

Sue thinks she’s figured out who Juan really is and confronts him at a Christmas party. But she’s wrong—he’s not in the mafia at all. However, it’s revealed that Sue doesn’t actually write her own Christmas letter.

After the excitement of the party, Lilly and Juan share some big kisses.

Juan gives Settie the Christmas letter she asked for, but she decides that she wants to write her own letter after all. The next day at breakfast, Settie reads the letter she wrote out loud, and it’s perfect—honest, heartfelt, and even admitting she hired a ghostwriter. She also explains how she fell back in love with Christmas, and how her family’s Christmas traditions are perfect just the way they are. The letter ends up winning the Christmas card contest, and we all cheer.