The Ruins by Scott Smith

Eerie, terrifying, unputdownable -- Scott Smith’s first novel since his best-selling A Simple Plan (“Simply the best suspense novel of this year -- hell, of the 1990s” -- Stephen King). The Ruins follows two American couples, just out of college, enjoying a pleasant, lazy beach holiday together in Mexico as, on an impulse, they go off with newfound friends in search of one of their group -- the young German, who, in pursuit of a girl, has headed for the remote Mayan ruins, site of a fabled archeological dig.

This is what happens from the moment the searchers -- moving into the wild interior -- begin to suspect that there is an insidious, horrific “other” among them...