Dodie owns an antique shop in a small town, where she spends most of her time daydreaming about love. One day, while rummaging through a storage unit, she discovers a box filled with vintage love letters, photographs, and trinkets belonging to a woman named Mildred. The box is addressed to Mildred's long-lost love, and Dodie becomes obsessed with finding the rightful recipient.
Dodie tracks down Mildred's grandson, Edward, who has recently moved back to town to renovate his grandfather's home. Edward is initially uninterested in Dodie's mission, but she eventually convinces him to help her search for the lost love. As they work together, Dodie and Edward develop a strong connection, and Dodie realizes that she may have found love in the most unexpected place.
Along the way, Dodie and Edward discover new clues to Mildred's love story, including the role that Edward's grandfather played in the romance. They also encounter various roadblocks, including a rival antique dealer who tries to thwart their efforts and a snowstorm that nearly derails their search.
In the end, Dodie and Edward find the recipient of the love box, and she is overwhelmed with emotion upon receiving the long-lost mementos of her past love. Dodie also realizes that she and Edward have fallen in love, and the two embrace in a romantic moment as the snow falls around them. A Very Vintage Christmas is a heartwarming tale about the power of true love and the magic of the holiday season.