In “Death on the Nile,” Hercule Poirot’s Egyptian adventure aboard a glamorous river steamer descends into a terrifying search for a murderer when an idyllic honeymoon is shattered by violent deaths. This sinister tale of obsessive love and its murderous consequences plays out in an epic landscape of danger and foreboding, with enough shocking twists and turns to leave audiences unsettled and guessing until the final, shocking denouement.