Maggie and Sam are crashing Christmas. When he proposes that they team up against his sister's perfect Christmas, neither of them are prepared for the blended family challenges that lie ahead.

At 12 years old, Carrie Watson places a piece of wedding cake under her pillow when her mother tells her about the superstition that doing so will ensure you dream of your future true love -- and that night, Carrie dreams of a handsome man meeting her at the altar. Fast forward a couple decades, and Carrie, now a successful chemist (and amateur baker), is prepping the wedding cakes for her little sister, Lydia's wedding. Carrie is shocked to discover that the groom's best man, Jason, is the very same man from her wedding cake dream.

No aniversário de Sarah, sua melhor amiga Victoria lhe dá um kit de teste genético de presente. Mas naquela noite, Victoria morre. Semanas depois, Sarah recebe a visita da polícia.

Elle's plans for Christmas reunion are thwarted by work. In order to get a career-altering promotion she's forced to team up with advertising campaign 'fixer' Max, who has a completely different take on the Holidays.