The Enchanted Forest is a land of magic. In the past decades, the political landscape has shifted greatly. King Xavier married his son, Henry, to a miller's daughter, Cora. Princess Eva married Prince Leopold. Both families had children. Princess Cora disappeared when her younger daughter, Regina, was two. The two young princesses, Zelena and Regina, have been raised by their father since. When Snow White was ten, her own mother, Princess Eva, died mysteriously.
Around that same time, Princess Zelena disappeared. Shortly after, Princess Regina married the now King Leopold becoming the stepmother to Snow White. Years passed and King Leopold died, leaving Regina queen of the land and Princess Snow a bandit. During the same time, King Midas's daughter, Abigail was betrothed to Prince James, son of King George whose lands were heading into bankruptcy.
Snow White and David now posing as his twin brother, Prince James, meet up and begin falling in love. Prince Charming, as he becomes known, leaves his betrothal to Princess Abigail and marries Snow White and the two of them wage war on the Evil Queen for control of the kingdom. They wrest the kingdom from her and banish Regina.
In retaliation for all she's lost, Regina casts an evil curse on the land, ripping everyone from their land and placing them in Storybrooke, living new lives. Time is frozen in this town and no one remembers yesterday happening.
On her 28th birthday, Emma Swan makes a wish on a cupcake, blowing out her birthday candle and setting into motion the events that bring her and others to Storybrooke. Emma's wish to not be alone any longer has unexpected consequences. Not only does it bring Henry to her door, it also brings various people to Storybrooke.
Shortly after Emma arrives in town, the clock starts to move and time starts anew.