The one thing a good whodunnit should not do is put its audience to sleep. Unfortunately, this latest cinematic adaptation of an Agatha Christie novel fails miserably on this score. Director Kenneth Branagh’s third outing as Belgian sleuth Hercule Poirot is a protracted snooze that leaves viewers caring little about the characters and even less about the story in which they’re trapped. When the famed detective (Branagh) – now in retirement in Venice – is called upon by a frie…























