portentous (adjective)

Portentous (por-TEN-tus) means serious; ominous. As used by Francine Prose: “What makes [Hillary Mantel’s] novels seem at once breezy and substantial is Mantel’s knack for leavening her weighty themes with seductive narrative strategies (suspense, portentous foreshadowing, hints of sinister and violent mysteries) that make the reader keep turning the pages.”