Shot on location in France and the British Isles, and based on an excoriating play by James Goldman, “Lion” is a wit-fueled, magnificently acted parable of power-lust and extreme family dysfunction. O’Toole and Oscar winner Hepburn are superb as the grizzled, sarcastic regent and his cunning wife, locked in a never-ending exchange of venomous criticisms. A youthful Anthony Hopkins, in a spirited turn, pops off some of the best insults. Aside from the endless machinations of various family members, Harvey adds period flavor with authentic costumes and gloomy, tone-perfect settings. When this “Lion” roars, you’ll be hooked.