Despite what its sexy previews suggest, Justin Chadwick’s “The Other Boleyn Girl” leaves audiences with the cinematic version of blue balls. We listen to Anne Boleyn (Natalie Portman) complain about the “degrading techniques” she must use to sexually arouse King Henry VIII (Eric Bana) and we see reaction shots of the witnesses at a beheading, but this trashy chick-flick could have been even more fun if it actually showed viewers the raunchy sex and the decapitated heads, rather than just teasing us to keep the PG-13 rating. Not to say that the film adaptation of Philippa Gregory’s novel isn’t entertaining. With plenty of bitchy banter, beautiful, lustful actors, melodrama and suspenseful plot twists, the film certainly qualifies as a guilty pleasure, but it isn’t quite pleasurable enough to completely satisfy the viewer.

We are conveniently told in the first scene that Anne Boleyn, the daughter and niece of two well-connected and power-hungry men, is a complicated person, while her younger sister Mary (Scarlett Johansson) is not, so the audience doesn’t have to think too hard to figure the characters out for themselves. Johansson is an expert at pouting and puppy-dog eyes, but she is careful not to overdo it, so it’s not difficult to see why King Henry would take notice of Mary’s sincerity the first time they meet. Likewise, there’s no mystery as to why Mary would fall for Eric Bana’s brooding yet tender king after she is forced to become his mistress, a role originally intended for Anne. Anne consequently feels so betrayed that she transforms from an independent, loving sister to a cruel, scheming seductress.

Anne returns from exile in France just as Mary is pregnant with the king’s first male heir, and she manages to completely steal away the king’s affection, seemingly by just telling unfunny, flirtatious jokes and refusing sex. But there is something very relatable and truthful about the scenes in which Mary and Anne bicker over their fickle male lover. Watching Anne pompously give relationship advice to her heartbroken sister should be an enraging experience for any girl in the audience who can recall the snide, catty and passive-aggressive days of female adolescence.

If this story, originally inspired by the real Tudor monarchy, was reworked into a modern-day teen drama, it would be a bore. But the exquisite costumes, monarchal politics and life-or-death stakes all help to create an addictive and mindlessly exciting viewing experience. Screenwriter Peter Morgan, who also penned “The Queen,” throws in some disturbing and over-the-top scenes toward the end, but the distant time period makes the historical fantasy feel believable and compelling.

Morgan’s script makes some weak attempts to take a stand against sexism and female rivalry, but it would have been wiser to treat the material just as King Henry VIII treats each mistress: as a disposable plaything without anything to say or any purpose beyond titillation.

Three stars