Nikolaj Arcel’s sweeping costume drama “A Royal Affair”—Denmark’s Oscar entry—follows the struggles of young Queen Caroline (Alicia Vikander) as she tries to adapt to her new role as wife of Denmark’s obviously insane King Christian VII (Mikkel Boe Folsgaard). The year is 1766, and Caroline, a native Brit, is forced to make do with her unpredictable husband and strange new surroundings with hardly any friendship or encouragement from the Danish court. She gives birth to a son, and it seems no one has any further use for her.

Eventually, the King hires a new doctor during a trip to Germany—Johann Struensee, played by Danish go-to Mads Mikkelsen. Caroline and Streunsee have an affair out of which results a daughter. Streunsee soon begins to wield power behind the throne and eventually convinces the King to cede all legislative power to him. In the thirteen months during which he practically had absolute sway over the affairs of the Kingdom of Denmark, he enacted sweeping reforms in favor of the peasantry and ordinary citizens, including education reform, universal vaccination, abolition of serfdom, suppression of torture and press censorship, to name a few.

Arcel’s film is beautifully shot and features lavish sets and costumes that recall the heyday of Merchant Ivory. Everyone turns in solid performances; Vikander is particularly compelling both as an ingenue and a jaded young queen, and Folsgaard deservedly won the Silver Bear at Berlin this year for his portrayal of the addled King. Arcel, who also wrote the script for the first (Swedish) iteration of “The Girl with the Dragon Tattoo,” has put together a serviceable, if lengthy (two hours and twenty minutes), screenplay that stays true to its historical details without letting them overwhelm the human drama at its center.

“A Royal Affair” reminded me of “The Duchess” (2008), a film which also centered on a controversial female aristocrat but that gave better voice to its protagonist’s pathos. Everything is as it should be, and yet I couldn’t escape the feeling throughout it all that there was some ineffable spark missing from this film. In fact, there were several times during the film when I found myself able to predict exact lines before they were spoken. “Affair” is a film so deeply invested in fulfilling its genre’s every convention that it seems to have forgotten to add something new to the costume-drama canon. While I can’t complain about any one of its well-conceived elements, “Affair” unfortunately ended up feeling distinctly less than the sum of its well-costumed parts.

“A Royal Affair” is Denmark’s foreign film entry at this year’s Academy Awards.