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 friend and author of murder mysteries (Tina Fey) to help her verify or discredit the psychic powers of a medium (Michelle Yeoh) at a séance at an allegedly haunted Venetian palazzo, he’s drawn into yet another of his famous investigations. The problem here is that what should be an engaging story is interminably dull, one that, regrettably, prompts frequent checking of one’s watch. Moreover, virtually the entire film is shot with excessively dark camera work (so much for showing off the glories of Venice). And then there are the performances, which feature good turns by Yeoh and Jude Hill but a positively wooden portrayal by Branagh (compared to his previous depictions of the protagonist) and an absolutely dreadful performance by a woefully miscast Fey. To its credit, like its recent predecessors, the production values of this Christie offering are top shelf, but that’s about all this release has going for it, a far cry from the much better overall work found in “Murder on the Orient Express” (2017) and “Death on the Nile” (2023). Indeed, even fans of the famed mystery writer are likely to find “A Haunting in Venice” tiresome and tedious. Pack a lunch for this one.