Fans of the ABC show "Once Upon a Time" might find it pleasantly surprising to know that new reports state that more characters from "Frozen" will be joining the cast next season.

The Season 3 finale revealed that Queen Elsa of "Frozen" will be joining the cast in the next installment. Reports from TVLine also mentioned that next season's cast will include Elsa's sister, Anna, in addition to the hunky mountain man, Kristoff. The same reports also mentioned that Elsa will be appearing in nine episodes, while the other characters from "Frozen" will be in fewer. The show's producers said they have started auditions to fill those new roles.

Other reports about the upcoming installment of the television series include spoilers about the relationship between Emma and Hook. According to International Business Times, the pair will be encountering some roadblocks in Season 4 despite the Season 3 finale's seemingly happy ending. Co-creator Adam Horowitz also mentioned in an interview with TVLine that "there will be some challenges" for Emma Swan and Captain Hook when the fourth season begins. Also, more Emma-Regina drama will surface, as Emma will be feeling guilty over how she destroyed Regina and Robin Hood's relationship. Horowitz said this will make her feel apprehensive about starting a new romance of her own. E! News further added that the ladies' rivalry will become "fierce" despite Emma's best intentions.

Season 4 of the American fairy tale drama series "One Upon a Time" will premiere in September on ABC. Reports have confirmed that it will be split in two: The first half will air in the fall, while the second half will air in the spring.