Just as Frankenweenie’s latest trailer reveals a darker side, so does this new one for DreamWorks’ Rise of the Guardians (Nov. 21). Jack Frost (Chris Pine) is a loner with no identity and so it’s tough recruiting him to join the Guardians of Childhood. Amid the splendor and excitement, there’s a Skywalker/Vader dynamic introduced between Jack and Pitch (Jude Law), the purveyor of nightmares. This looks better and better. Director Peter Ramsey has reason to rejoice.