On her 28th birthday, Emma Swan meets Henry, the son she gave up for adoption 10 years ago. Henry believes Emma is the daughter of Snow White and Prince Charming, prophesied to break a powerful curse. Unconvinced, Emma returns Henry to Storybrooke, where she encounters the enigmatic Mr. Gold and clashes with mayor Regina Mills, the boy's adoptive mother, who Henry insists is none other than the Evil Queen!

It's a diabolical thing about curses: Just as one is broken, another, even more sinister than the first, inevitably emerges to wreak further havoc. The stakes are higher than ever following a narrow escape from the nightmare of Neverland and Peter Pan. A year after their amazing adventure, Emma and Henry are living in New York with no awareness of their past history- until Hook shows up and jogs Emma's memory with a magic potion. Once again, the "Savior"...

Soon after Emma and Hook unwittingly bring Elsa of Arendelle to Storybrooke, they encounter the mysterious "Snow Queen," whose relentless obsession with both Emma and Elsa has chilling consequences. Meanwhile, it appears Regina has at last found true love with Robin Hood, but how will she react when her happy ending is thwarted yet again by a maddening, seemingly pre-ordained twist of fate?

In times of national emergency, a team of Britain's leading experts, crisis contingency planners and most senior politicians from the corridors of Whitehall to the salons of No. 10 Downing St. assemble under the name COBRA to coordinate the response

When the Savior becomes the "Dark Swan," the lines between good and evil blur as Emma begins to relish the intoxicating taste of absolute power. Terrified she'll succumb, Emma and Hook visit Camelot to find the one person who may be able to aid them: Merlin. Unfortunately, King Arthur proves treacherous, and when he joins forces with a vengeful Zelena, Emma and Hook's hopes are shattered