Harbingers (Book 1) Gathering four stories from four bestselling author friends, Invitation is the first collection in the new Harbingers series.In "The Call" by Bill Myers, four strangers are drawn together to help a student at the mysterious Institute for Advanced Psychic Studies. Frank Peretti''s "The Haunted" is a supernatural murder mystery, while in Angela Hunt''s "The Sentinels" animals around the world are mysteriously dying. And "The Girl" by Alton Gansky is a gripping tale of a young barefoot girl found holding a scroll in the snowy Oregon mountains.