A Tale of Two Sisters

"A Tale of Two Sisters" is the first episode of the fourth season of the American fantasy drama series Once Upon a Time, which aired on September 28, 2014. The episode introduces several characters from the 2013 film Frozen to the series. The episode also has the characters deal with the consequences of Emma Swan (Jennifer Morrison) and Killian "Hook" Jones's (Colin O'Donoghue) time traveling in the third season finale. Commentators gave generally positive reviews for the premiere, with most complimenting the new characters and the new direction the series was taking; however, some felt that the series was capitalizing too much on the success of the episode's source material. Upon airing, the premiere was watched by 9.47 million viewers and attained an 18-49 rating of 3.5. This marks a significant increase in viewership and ratings from the previous season premiere. Plot