Each December, as the temperatures fall, a frost fair takes place at the command of Queen Frostiana. For the community of little mice, it is a time of great excitement and fun. But one year, a magical, little mouse called Mistletoe-Merry becomes separated from her family due to the mayhem caused by the Spirit of Winter Mischief. She befriends young Henry and the two set off on a series of daring adventures to try and find her family. Can they find them in time before the ice melts? Will a thrilling rescue attempt of a former enemy put all their lives in danger? A heart-warming tale to delight children with magic, friendship, and forgiveness in the coldest time of the year.