Bøger i The Rosenholm Trilogy serien

Four girls receive invitations to apply for a school they've never heard of and make it through the unusual testing process to find themselves placed in a magical boarding school for students with powers. Once the school year begins, a young woman's spirit urges the new girls to solve her murder which has been cold since the 1980s -- but unbeknownst to them, doing so will put them in mortal danger.