No one knew about Ariella Potter, not even her half brother the famous Harry Potter. It wasn't until Harry's fourth year in Hogwarts that he met his sister. Things were going to be difficult for Ariella, who wasn't like her other housemates. She was faster, stronger and more powerful. However this would be put to the test as dark forces try to infiltrate her mind to try and persuade her to join Voldemort's Army. Will she crack under the pressure or will a certain student be all she needs?