By JUSTIN CHANG

A Warner Bros. release, presented in association with Legendary Pictures, of a Syncopy production. Produced by Emma Thomas, Charles Roven, Christopher Nolan. Based upon characters appearing in comicbooks published by DC Comics, “Batman” created by Bob Kane.

Having memorably explored the Caped Crusader’s origins in “Batman Begins,” director Christopher Nolan puts all of Gotham City under a microscope in “The Dark Knight,” the enthralling second installment of his bold, bracing and altogether heroic reinvention of the iconic franchise. An ambitious, full-bodied crime epic of gratifying scope and moral complexity, this is seriously brainy pop entertainment that satisfies every expectation raised by its hit predecessor and then some. That should also hold true at the box office, with Heath Ledger’s justly anticipated turn as the Joker adding to the must-see excitement surrounding the Warner Bros. release

With the Bruce Wayne/Batman backstory firmly established, “The Dark Knight” fans out to take a broader perspective on Gotham City — portrayed as a seething cauldron of interlocking power structures and criminal factions in the densely layered but remarkably fleet screenplay by helmer Nolan and brother Jonathan (stepping in for “Batman Begins’” David S. Goyer, who gets a story credit).

Using five strongly developed characters to anchor a drama with life-or-death implications for the entire metropolis, the Nolans have taken Bob Kane’s comicbook template and crafted an anguished, eloquent meditation on ideas of justice and power, corruption and anarchy and, of course, the need for heroes like Batman — a question never in doubt for the viewer, but one posed rather often by the citizens of Gotham.

Indeed, with trusty Lt. Jim Gordon (Gary Oldman, superbly restrained) and golden-boy District Attorney Harvey Dent (a cocksure Aaron Eckhart) successfully spearheading the city’s crackdown on the mob, even Wayne himself (Christian Bale) figures his nights moonlighting as a leather-clad vigilante are numbered. The young billionaire hopes to hang up the Batsuit for good and renew his relationship with assistant D.A. Rachel Dawes (Maggie Gyllenhaal, an immediate improvement over Katie Holmes), who has taken up with Dent in the meantime.

But Batman’s stature as a radical symbol of good has invited a more sinister criminal presence to Gotham City — and, as seen in the crackerjack bank-robbery sequence that opens the pic, one who operates in terrifyingly unpredictable ways. Utterly indifferent to simple criminal motivations like greed, Ledger’s maniacally murderous Joker is as pure an embodiment of irrational evil as any in modern movies. He’s a pitiless psychopath who revels in chaos and fears neither pain nor death, a demonic prankster for whom all the world’s a punchline.

After Ledger’s death in January, his penultimate performance (with Terry Gilliam’s “The Imaginarium of Doctor Parnassus” still to come) will be viewed with both tremendous excitement and unavoidable sadness. It’s a tribute to Ledger’s indelible work that he makes the viewer entirely forget the actor behind the cracked white makeup and blood-red rictus grin, so complete and frightening is his immersion in the role. With all due respect to the enjoyable camp buffoonery of past Jokers like Cesar Romero and Jack Nicholson, Ledger makes them look like — well, clowns.

The pic shrewdly positions the Joker as the superhero-movie equivalent of a modern terrorist (one of several post-9/11 signifiers), who threatens to target Gotham civilians until Batman reveals his identity. Batman, Gordon and Dent uneasily join forces, but the Joker seems to have the upper hand at every step, even from a jail cell; the city, turning against the hero it once looked to for hope, seems more fractious, vulnerable and dangerous than ever.

Though more linear than “Memento” and “The Prestige” (both also co-scripted by the Nolans), “The Dark Knight” pivots with similar ingenuity on a breathless series of twists and turns, culminating in a dramatic shift for Dent. This subplot reps the film’s weakest link, packing too much psychological motivation into too little screen time to be entirely credible. Yet Eckhart vividly inhabits the character’s sad trajectory, underscoring the film’s point that symbols of good can be all too easily tarnished.

From Wayne’s playful debates with faithful butler Alfred (Michael Caine) about the public perception of Batman to the Joker’s borderline-poetic musings on his own bottomless sadism, the characters almost seem to be carrying on a debate about the complicated realities of good vs. evil, and the heavy burden shouldered by those fighting for good. One of the few action filmmakers who’s capable of satisfying audiences beyond the fanboy set, Nolan honors his serious themes to the end; he bravely closes the story with both Gotham City and the narrative in tatters, making this the rare sequel that genuinely deserves another.

Viewers who found “Batman Begins” too existentially weighty for its own good will be refreshed to know that “The Dark Knight” hits the ground running and rarely lets up over its swift 2½-hour running time. Nolan directs the action more confidently than he did the first time out, orchestrating all manner of vertiginous mid-air escapes and virtuosic highway setpieces (and unleashing Batman’s latest ooh-ah contraption, the monster-truck-tire-equipped Bat-Pod). In a fresh innovation, six sequences were shot using Imax cameras, and will presumably look smashing in the giant-screen format (pic was reviewed from a 35mm print).

Though not as obsessively detailed as “Batman Begins,” “The Dark Knight” shares with that film a robust physicality and a commitment to taking violence seriously; a brief shot of bruises and scrapes on Bale’s torso conveys as much impact as any of the film’s brutal confrontations. Bale himself is less central figure than ensemble player, but the commandingly charismatic thesp continues to put his definitive stamp on the role, and also has devilish fun playing up Wayne’s playboy persona.

Tech work is at the first entry’s high standard, with many artists reprising their contributions here — from Nathan Crowley’s imposing production design, shown to flattering effect in Wally Pfister’s gleaming widescreen compositions, to the propulsively moody score by Hans Zimmer and James Newton Howard. Perhaps most impressive is Lee Smith’s editing, confidently handling multiple lines of action and cutting for maximum impact.

Exteriors were lensed in Chicago aside from an early, plot-necessitated detour to Hong Kong, which marks the first time in a Batman film that the title character has left Gotham City.

Reviewed at Warner Bros. Studios, Burbank, July 3, 2008.
Rating: PG-13. Running time: 152 MIN.