NANCY DREW IS AN AMATEUR DETECTIVE LIVING IN RIVER HEIGHTS. HER FATHER—CARSON DREW IS A FAMOUS LAWYER JUST AS SHE IS FAMOUS. IN THIS STORY, NANCY AND HER BEST FRIENDS—GEORGE FAYNE AND BESS MARVIN ARE ON A TOUR TO IRELAND, WITH A TOUR GROUP NAMED—MCELHENEY TOURS. THE OTHER MEMBERS OF THE TOUR ARE—CARL THOMPSON WHO IS A CHEMIST FROM BOSTON, JIM AND NATALIE DE FUSCO FROM CALIFORNIA. THERE IS ALSO RHONDA AND RACHEL SELKIRK FROM AUSTRAILIA AND DEREK THOROGOOD AND CAMILLA COLLINS FROM ENGLAND.
NANCY AND HER FRIENDS ARE LOOKING FORWARD TO SPECTACULAR SCENERY, ROMANTIC RUINS, LOCAL ENTERTAINMENT, AND AT THE END OF THE DAY, COZY INNS. BUT THINGS ARE NOT WHAT THEY SEEM. SOMEONE IS TRYING TO HURT THE SELKIRK GIRLS FROM THE BEGINNING OF THE TOUR.
DEREK AND TERRY O’ LEARY—THE CARAVAN DRIVER ARE ACTING VERY SUSPICIOUS. THERE IS ALSO AN AUSTRAILIAN MAN IN BLACK SUIT WHO IS FOLLOWING THE TOUR GROUP. BUT WHO OUT OF THE THREE PEOPLE IS THE REAL CRIMINAL? AND WHAT IS HIS INTENTION? AS THE GROUP BIKES ALONG THE STEEPEST SLOPES AND SHEEP-FILLED ROADS, NANCY KNOWS THAT IF SHE MAKES ONE WRONG MOVE SHE WILL BE IN GRAVE DANGER!