A séance, a murder, an unsolved mystery…what else does an unforgettable Halloween party need? Kenneth Branagh’s “A Haunting in Venice” adapts Agatha Christie’s novel “Hallowe’en Party” for a supernatural thriller with an all-star Oscar-winning cast behind the whodunit. Branagh, who directs, returns as famed detective Hercule Poirot, whose retirement is bungled after a party guest is murdered.