The Magician's Box (The Gormengate Chronicles Book 1)

After the mysterious disappearance of their great uncle Wilfred, Alex and his brother David must spend the last week of the summer holidays in a decaying old mansion inherited by their parents. While exploring the derelict house, Alex finds an ancient box that seems to defy the very rules of the natural world. Is he going crazy, or has he just discovered a door to strange and dangerous parallel universe?