The Hidden Oasis opens in 2152 BC with eighty priests setting out under cover of darkness into Egypt's Western Desert, dragging with them a sled on which rests a mysterious object swathed in cloth. Four weeks later, having reached their destination, the priests calmly slit each other's throats.

Four thousand years later in present-day Egypt, professional rock climber Freya Hannen arrives for the funeral of her sister, Alex, a Saharan explorer. From the outset, Freya is suspicious of claims that Alex had taken her own life, and sets out to uncover what really happened to her sibling. In her quest for the truth Freya joins forces with Alex's friend, English academic Flin Brodie, a world authority on the prehistory of the Sahara. Flin is also searching for answers—he has devoted his career to tracking down a mythic hidden oasis.

In this propulsive, nail-biting thriller—all the more engrossing because Sussman himself has worked extensively as an archaeologist in Egypt—we follow Flin and Freya on an unforgettable adventure.At stake are not simply the answer to one of archaeology's greatest mysteries—the location of the legendary lost oasis of Zerzura—but also the key to the astonishing, terrifying secret that lies at the oasis's heart.