Anne Forbes 
The Underground City [EPUB ebook] 

On the eve of his return to Scotland, Lewis Grant is dared to spend the night at the haunted desert oasis of Al Antara. But things don’t go according to plan and on Lewis’ subsequent arrival in Edinburgh, strange things start to happen. Set against the spooky backdrop of Mary King’s Close, Neil and Clara Mac Lean find themselves embroiled with the enigmatic Lewis, frightened ghosts, reckless bank robbers and a very cranky djinn. Enjoy a third outing for the Mac Arthurs and their dragon, as monsters and mayhem return in a breathtaking tale of magic and nightmare.