“The Nun 2” and “A Haunting in Venice” were neck and neck at the top of the North American box office, with the horror sequel taking a slight lead. “The Nun 2” grossed $14.7 million in its second weekend, while “A Haunting in Venice” opened with $14.5 million. Warner Bros.’ “The Nun 2” is expected to retain the top spot for the second consecutive week. Kenneth Branagh’s “A Haunting in Venice” may have struggled to match the success of his previous Agatha Christie adaptations.