On Princess Ella of Charmante's twenty-first birthday, she willingly enters an Enchanted Forest portal; she is ready to return home after she studied abroad in a different realm. While she'll miss her new friends, she is eager to return to her old life.
Instead of returning her to Charmante, the Enchanted Forest leads Ella to a forgotten kingdom beneath the earth. Within this kingdom's depths, she meets eleven ladies and the twelve cursed stag-men they are meant to dine and dance with every night until midnight.
After being separated from his siblings, Prince Thomas of Roschen is guided by the Enchanted Forest to a cave. When he emerges, he finds himself in a kingdom cursed to be forgotten.
Once the old friends are reunited, Ella and Thomas have to work together to break the spell trapping Ella and the others in Verloran. Will they succeed and free both the ladies and the stag-men, or will they fail and their existences be forgotten over time.
The Forgotten Kingdom is a mix of Cinderella meets the Twelve Dancing Princesses.