Successful yet recluse author Harrington returns to his hometown for an annual Christmas festival, where he must face his publicist there for damage control.

A chance meeting between two strangers who share a disdain for Christmas results in The Mistletoe Promise, a pact to help them navigate their holiday complications – together. But as they spend more time with each other and experience the magic of Christmas the phony couple discovers there may be more to their contract than business.

Following a fall during mistletoe picking, Druid Getafix decides that it is time to secure the future of the village. Accompanied by Asterix and Obelix, he undertakes to travel the Gallic world in search of a talented young druid to transmit the Secret of the Magic Potion.