An inexplicable explosion rocks the antiquities collection of a London museum - and sets off alarms in clandestine organisations around the world...The SIGMA Force debut from the NEW YORK TIMES bestselling author of MAP OF BONES and THE DOOMSDAY KEY. Lady Kara Kensington's family paid a high price in money and blood to found the gallery that now lies in ruins. And her search for answers is about to lead her into a world she never imagined existed: a lost city, buried beneath the Arabian desert, where something astonishing is waiting... A covert government operative hunting down a traitor is being drawn there. But at the end of a perilous journey lies an ageless power that can create a utopia - or tear down everything humankind has built over millennia of civilisation...