Mosaic City, located along China's coast, is quite large city sometimes called the Crossroads Between Nations due to its diverse population. While it was once a large tourist spot, the city was placed under a blockade as the military appeared claiming there was a radiation leak. The true hazard, however, is much more sinister.
After Emma and Killian managed to return to Storybrooke from the past, they accidentally returned with Elsa, the Snow Queen. After being locked up by Rumplestiltskin for a very long time, Elsa has a bit of a grudge against him. She will stop at nothing to make him suffer for what he did to her. She was captured long ago and because of Rumplestiltskin, she will never see her sister Anna again, who died while Elsa was captured by the Dark One.
Meanwhile, with the return of Maid Marian, Robin Hood now must choose between the person he was fated to be with and the person who is the mother of his child. Other relationship drama, like Rumplestiltskin hiding the fact that Belle doesn't really have his dagger and that he killed Zerena the Wicked Witch when he wasn't suppose to is also happening.
After the birth of the Royal Son, Neal, the Charming's are finally happy, and Emma and Henry have finally found their home. But what will happen when the Snow Queen decides to enact her revenge on the citizens of Storybrooke. Will the heroes be able to fend her off like they did all the other threats in the past, or are they all truly doomed this time once and for all?