Little time elapses before we perceive that Harry Potter has gone up a grade — and not just at Hogwarts School of Witchcraft and Wizardry. No sooner has Fiona Shaw’s Aunt Petunia put the finishing touches on a pastel pudding meant for company and Richard Griffiths’s Uncle Vernon, a mountain in a tight suit, sent young Harry to his room than the fledgling wizard is confronted by a computer-generated entity far less cheesy than the Lord-Voldemort-as-talking-turtle who appeared at the climax of Harry Potter and the Sorcerer’s Stone. There on Harry’s bed is Dobby the house elf, an emaciated, dirt-streaked figure in a filthy tea towel, his great eyes bulging with agitation, his Yoda ears flexing like biceps. With his endless, obsequious hand wringing and head banging, Dobby will irritate some. But he’s a Star Wars–worthy little goober nonetheless, and a major player in Harry Potter and the Chamber of Secrets, the second film to be built on J.K. Rowling’s phenomenally successful series of novels about the danger-fraught education of a wiz kid.

Despite its inventive use of an old diary as a vehicle for time travel, Harry Potter and the Chamber of Secrets, with such horror-movie standards as giant spiders and a serpent in the plumbing, is the weakest of the Harry Potter novels so far. But director Chris Columbus has made a darker, quicker movie of it than he did of The Sorcerer’s Stone, with particularly fine settings and atmosphere. This film, too, stints on the eccentric, Etonian detail of Hogwarts (though having folks frisk about in moving portraits remains amusing). Still, given that the basic relating of Rowling’s plot, to which the film slavishly adheres, requires 162 minutes, there’s hardly time for pumpkin juice or Nearly Headless Nick’s deathday party.

Here in round two, after a brisk bit of Dursley bashing and the introduction of Dobby, Harry is rescued from his punitive home on Privet Drive by fellow wizard students Ron, Fred, and George Weasley, who’re driving dad Arthur’s beat-up flying Ford Anglia. When Harry and Ron are mysteriously unable to cross through the barricade to the magical platform from which the Hogwarts Express leaves London’s King’s Cross Station, the two fly the car to Hogwarts. There it survives a battering collision with an impressive bit of pugilistic flora called the Whomping Willow (a fate one might better wish on relentless composer John Williams, though his volume is turned down from The Sorcerer’s Stone).

The hot water this lands the lads in is nothing to what follows, which includes a murder-bent voice in the walls that only Harry can hear and a mysterious set of attacks that leave several students and the nasty caretaker’s cat petrified. Moreover, Harry must endure the fawning of foppish new Defense Against the Dark Arts teacher Gilderoy Lockhart and the ostracism of students who fear that, because he can talk to snakes, Harry may be the menacing, messaging "heir" of rogue school founder Salazar Slytherin. It is Slytherin who is thought to have carved out the secret catacomb of the title, the reputed home to a heinous monster — which, in the film’s harrowing climax, turns out to be formidable indeed. (The same cannot be said of the galloping army of arachnids that, though creepy, seem implausibly numerous and bounding.)

There are a couple of ways in which Columbus’s film improves on the book. The preening Lockhart, a grating presence in Rowling’s rendering, is given goofy comic brio by a wavily coiffed Kenneth Branagh, who’s garbed in a series of flourishy get-ups. And Alan Rickman adds a brooding quizzicality to the spitefulness of oleaginous Potions professor Severus Snape.

The late Richard Harris is pale and breathy but continues to exude sly, gentle wisdom as headmaster Albus Dumbledore, and Maggie Smith is back, in all her pursed authority and Scottish cadence, as prim deputy headmistress Minerva McGonagall. A marvelously sinister addition to the extracurricular populace is icy Jason Isaacs as Lucius Malfoy, father of Harry’s arch-enemy Draco, abuser of Dobby, and chief proponent of ethnic cleansing (of Muggle-borns) at Hogwarts. Add a clipped moustache to his long platinum locks and this Malfoy would be an apt cross between Hitler and Fabio. Among the trio of child actors at the heart of the story, Daniel Radcliffe has gained grit and gravitas as Harry, and Emma Watson continues to exude precocity as the brainy Hermione. But mugging Rupert Grint, so personable as Ron in The Sorcerer’s Stone, appears to have studied too long at the Macaulay Culkin School of Home Alone acting, Chris Columbus, headmaster.