While this drama has nothing new to say about the challenges of dementia, it does present the difficulties resulting from that illness in an innovative way. In adapting his play with co-screenwriter Christopher Hampton, director Florian Zeller portrays the mental confusion of a man in his 80s (Anthony Hopkins) by keeping the viewer off-balance as well. Thus Hopkins’ character sometimes sees different women (Olivia Colman or Olivia Williams) as the daughter with whom he lives. And he’s often taunted by a strange man (Mark Gatiss) who announces that he also lives in their London apartment. Skillfully understated performances by Hopkins and Colman make this a deeply moving experience, especially for anyone who has cared for an elderly parent at home. Though some may see the proceedings as having a somewhat polite veneer — the protagonist is never violent, only fearful like a child — the film is admirably courageous in other respects, delving into moral depths and laying bare family relationships. Mature themes, fleeting coarse language. The Catholic News Service classification is A-III — adults. The Motion Picture Association rating is PG-13 — parents strongly cautioned. Some material may be inappropriate for children under 13.