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.

After being struck by lightning, CSI investigator Barry Allen awakens from a nine-month coma to discover he has been granted the gift of super speed. Teaming up with S.T.A.R. Labs, Barry takes on the persona of The Flash, the Fastest Man Alive, to protect his city.