Last day of a Normal Life

Two Twins, brother and sister, named Freya and Klaus, thought they had a normal life, until one day there parents went missing and found out that the life of their parents lay on their hands. What will they do? Luckily they weren't alone on this, as they had someone to help them, and fight evil with their magical powers, although they were new at this, they didn't have much time! Will they have the power to save their parents? Will they survive? Does evil win or lose?