Many years ago, Queen Ondine quarreled with the Mistress of the Underground Kingdom. The evil witch promised that the queen would not have grandchildren. And if it does, the child will bring a lot of grief to the royal family. But the long-awaited heiress - Princess Lucky - was finally born. However, during the christening of the beautiful baby, a terrible prophecy was made: the princess will die on the day she comes of age! The evil witch did not foresee one thing: the good fairy Blue Star managed to put a magic amulet on Lucky’s finger... Years passed, the princess grew up and became a dazzling beauty. But the terrible day of coming of age came. Will the terrible predictions come true?..