If a film such as “The Irishman” or “Once Upon a Time in Hollywood” is unnecessarily long, then what will people say about “Malmkrog,” Cristi Puiu’s three-and-a-half-hour period adaptation? Focused almost entirely on the intellectual discussions of five aristocrats gathered at a wintry Transylvanian mansion in the early 1900s, “Malmkrog” belongs to the milieu of cerebral art-films whose arduousness is perhaps exactly the point. Cinephiles with a taste for the hardcore, painful pleasures of slow cinema, are encouraged to read further, but it’s difficult to recommend this feature to the movie-goer unacquainted with or baffled by the sorts of films in which “nothing happens.” Imagine “My Dinner With Andre” without the intimacy and zany charisma. By contrast, Puiu’s interlocutors remain at a distance, heightened by the filmmaker’s surreal flourishes. In any case, should you be willing to embrace its formal provocations and intentional tedium, the film offers a bewitching, and deeply haunting experience, one that ambitiously probes the relationship between language and history.