A short, trippy teaser for David Fincher's upcoming film adaptation of The Girl With the Dragon Tattoo — the best-selling first installment of Stieg Larsson's Millennium trilogy, which has already been turned into an acclaimed 2009 Swedish movie — was released to much hype earlier this summer. Now a full three-and-a-half-minute trailer is out (see the video below), offering the first proper look at Social Network star Rooney Mara's performance as the darkly enigmatic heroine Lisbeth Salander, and Daniel Craig's take on the troubled journalist Mikael Blomkvist. The trailer also begins introducing newbies to the film's many disturbing, violent plot twists — nearly all of which center around the investigation of an unsolved decades-old murder. Tattoo will hit theaters Dec. 21. Now that the trailer has been released, here are five things critics are buzzing about:

1. Rooney Mara transforms herself as Lisbeth
In the original film, Noomi Rapace's performance as Lisbeth Salander was "rigidly stoic," says Megan Gibson at TIME. Judging from the trailer, Rooney Mara will show "about an ounce of vulnerability," which will likely play well with American audiences. The actress seems to have disappeared into the role, says Ben Child at the U.K.'s Guardian. The sweet-faced, mild-mannered Mara is "unrecognizable as Salander, especially with that Scandanavian lilt." Indeed, she "seems to vindicate" the decision to shoot the film in Swedish-accented English, says Matt Maytum at Total Film.

2. The film will be very, very dark
While the trailer certainly previews the film's violent story, it doesn't come "close to warning how graphic things get," says Gibson. For those unfamiliar with the source material, "there's likely to be a sobering shock" when they witness just how brutal the film is. But we're in good hands with Fincher, says Jacqueline Burt at The Stir. The "Fincher-esque menace is visual," and the same "rough-around-the-edges, slightly off-balance" treatment he used to make the violence in Se7en so dynamic and thrilling appears is display here.

3. The score is haunting
Trent Reznor and Atticus Ross, who won an Oscar for their foreboding Social Network score, have complemented the disturbing plot with their "haunting electronica soundtrack," says Sandy Schaefer at Screen Rant. Others note that the score really succeeds in setting the tension between Mara and Craig.

4. It looks better than the Swedish film
"Brooding" and "precise," the trailer makes Fincher's take on Tattoo look "far more engaging that the original Swedish" version, which, though a perfectly fine film, "always maintained the whiff of leisurely Sunday evening" TV show, says Child. Indeed, Fincher hits the "perfect tone of intrigue, suspense, and tension," says The Inquisitr. Still, there's no escaping the feeling that "we've seen it all before," says Steven Zeitchik at the Los Angeles Times, which makes one wonder if there's a point to making another film at all.

5. And could actually live up the intense hype
Stark, intense, and previewing compelling performances from Mara and Craig, the trailer "seems to live up to the already considerable hype" for the film, says Gina Serpe at E! Online. The trailer now cements the surefire blockbuster as an Oscar contender, says Tom O'Neil at the Los Angeles Times. Academy voters love "overdue, cool directors with edgy new films," and Mara should find herself a strong candidate for lead actress, judging by this clip. "My prediction," says Burt, is that Mara is "going to EXPLODE after this."