Ann-Marie MacDonald is a Canadian Governor General's award-winning playwright, and Fall on Your Knees (Knopf, $27.99 in Canada) is her first novel. MacDonald's epic is bleak but ultimately triumphant as it uncovers the unlovely secrets of a Cape Breton family: the Gaelic-speaking Scot, James Piper, his Lebanese Catholic child-bride, Materia, and their four invincible daughters, Kathleen, Mercedes, Frances, and Lily. This is Dickens with poetry.