Lene Kaaberbol and Agnete Friis are the Danish duo behind the Nina Borg series. Friis is a journalist by training, while Kaaberbol has been a professional writer since the age of fifteen, with more than two million books sold worldwide. Their first collaboration, The Boy in the Suitcase, was a New York Times and USA Today bestseller and has been translated into twenty-seven languages.
Katherine Kellgren has appeared onstage in London, New York, and Frankfurt. Her work includes the role of Laura in a regional production of The Glass Menagerie and appearances on Comedy Central. She is an Audie Award-winning narrator of audiobooks and has also received the Peabody Award and forty-two AudioFile Earphone Awards.