Bobbie Peers 
William Wenton and the Secret Portal [PDF ebook] 

The second book in the gripping fantasy-adventure series, packed with code-breaking, cyber-technology and a boy hero with a supernatural destiny.Twelve year-old genius William Wenton is still getting used to his extraordinary talent for cracking codes, but when an ancient artefact mysteriously disappears from the Depository for Impossible Archaeology, William must gear up for his most dangerous adventure yet — against an enemy hell-bent on unleashing an ancient portal of untold power. From Norway, to England and then to the dizzying heights of the Himalayas, this race-against-time adventure will push this young hero’s skills to the limit.