The only thing better than a dame is a creepy dame. The dame in question, Judi Dench, has made a name for herself by defying monarchial sanction in roles as diverse as Bond’s faithful boss M and the proprietor of a scandalous strip show in “Mrs. Henderson Presents.” This time, director Richard Eyre draws a ponderously intense (and Oscar-nominated) performance from Dench, who plays the fanatically infatuated schoolmarm Barbara Covett in “Notes on a Scandal” — and, as Covett says, “oh, what a marvelous intensity it is.”

The film charts in chilling detail the fluctuations in the unstable relationships between disparate and intriguing characters. Cate Blanchett is Sheba Hart, the seemingly naïve bourgeois bohemian art teacher unable to control both her students and her dissatisfaction with the monotony of life with her posh older husband, played by Bill Nighy. A leprechaun-like Steven Connelly is Cate Blanchett’s “pubescent paramour,” a mere 15-year-old who courts his teacher with feigned stories of trouble at home and graphically sexual text-messages. Covett lurks behind it all, recording secrets in her diary until she can use them to manipulate those around her and claim Blanchett for herself.

“Notes on a Scandal” is, in essence, a film about the various ways humans seek comfort and diversion to dispel disillusionment with life. It is about striking a compromise between morality, and the pursuit of personal satisfaction. While Covett employs meticulous restraint in her pursuit of Hart, Hart throws herself into her illegal affair with total visceral abandon. No character in “Notes on a Scandal” is innocent: Everyone is instead self-serving, building around themselves fortifications of selfish lies and secrets that ultimately crumble. Yet their errors, their fallibility, make these people sympathetic, human, although in no way enviable.

This film is truly thrilling and derives its suspense as much from inaction as from action — as much from the invisible claws of blackmail as from sexually salacious intrigue. As Covett herself says, she is out to “gain everything by doing nothing.” This tension is heightened by the film’s soundtrack, composed by Philip Glass, which is so riveting that even if the film were not terrifyingly suspenseful in its own right (which it is), the score would have you violently squeezing the arm of your chair (or of your date). The haunting percussion of the song “Someone in Your Garden,” petrifies me even in the comfort of my own common room.

Dench’s performance glints brilliance from that first cunning twinkle in her eye to her last possessive fit, and Blanchett shines with the subtle glow of an actress expertly playing “the wispy novice.” There is no need to fear, however, that Blanchett will limit her character to a preyed-upon sap with “the complexion of a white peach”: When she discovers Covett’s journals, Blanchett’s Hart ultimately throws quite the vengeful tantrum, combining the banshee-esque antics of Courtney Love and Nancy Spungen.

But if you’re not about to abandon the stress of your own life in order to take on the stress of fictional characters, there is still something in this movie for you. Dench’s narration of the diary entries offers a privileged window into the thoughts of a troubled woman: Basically, you get to hear a dame being very, very bitchy. And everyone knows that the only thing better than a creepy dame is a bitchy dame.