David O. Russell may not want to have this announced publicly, but Saturday's Toronto International Film Festival brought us a new heavyweight in the Oscar race.

"The Silver Linings Playbook," Russell's first movie since the Oscar-nominated "The Fighter" two years ago, came to Toronto without much buzz but debuted on Saturday night in Roy Thomson Hall to a roaring ovation.

Featuring a career-changing performance from Bradley Cooper (Ieft with David O. Russell and producer Jonathan Gordon) and another brilliant one from Jennifer Lawrence, "Silver Linings" is a perfectly calibrated comedy that is also deeply moving; it's another major step in Russell's comeback from movie limbo, and a mainstream film with enough heart and clout to immediately figure into a number of Oscar races, definitely including Best Picture.

That it debuted without the advance hype of more heralded contenders like "The Master" and "Argo" was a plus for Russell, the director told TheWrap at a Soho House party after the screening.

"I like being the underdog," he said between accepting congratulations on his film. "Now we just have to see if we can stay the underdog for the next two months."

That much, at least, seems unlikely, though the Academy's bias against comedy may prevent "Silver Linings" from becoming a frontrunner.

Russell said he wrote the script before making "The Fighter" but couldn't get the film off the ground until the latter film's success made it possible. "[The late producer/director] Sydney Pollack sent me the book [by Matthew Quick] years ago and said the tone would be very tricky," Russell said of the story of a man whose anger-management issues have sent him into a mental institution and the damaged young woman with whom he strikes up an uncomfortable friendship. "But I knew that family, and I understood the issues."

While Russell said he sees the film as a companion piece to "The Fighter," in which he emphasized up the family dynamic that had been played down in the original script, it also harkens back to the director's earlier, comedy-oriented films like "Flirting With Disaster."

In fact, the comedy played so well at Roy Thomson Hall that Russell facetiously bemoaned the fact that one of the most sure-fire laugh lines from Robert DeNiro (in his meatiest role in years) was drowned out because the audience was applauding an earlier line by Lawrence.

"That's not really a problem to complain about," he conceded.

Speaking of important lines, there was one that fell about two-thirds of the way through "Cloud Atlas," the Wachowskis' and Tom Tykwer's gloriously maddening time-traveling sci-fi epic that also premiered in Toronto on Saturday night: "All boundaries are conventions made to be transcended."

"Cloud Atlas" transcends Hollywood boundaries, all right – to the point where it has left some viewers calling it the year's best movie and sent others out of the theater long before its near-three-hour running time ends.

After seeing the film at a private screening first thing in the morning on Saturday, I have no idea if it is complete folly for Warner Bros. to be releasing what could easily be a commercial flop, or if WB is brilliant for backing (reportedly without a substantial investment) a twisted landmark.

More than a decade after "The Matrix," the Wachowskis (brothers no longer, as you may have heard) have teamed up with "Run Lola Run" director Tykwer to tell one big, long, goofy three-hour story that constantly jumps between six different time periods and six different sets of characters – though in many cases, it's the same actors playing different people in different times, from a couple hundred years in the past to a couple hundred in the future.

(Several of the actors – interestingly enough, given the former Larry Wachowski's recent transition to Lana Wachowski – play both male and female roles. Warning: the sight of Hugo Weaving as a Nurse Ratched type is not a pretty one.) 

(From left: Andy Wachowski, Lana Wachowski and Tom Tykwer)

Most of the scenes, I'd guess, last less than a minute before the action jumps to a different time; it takes quite a while to come together into any semblance of cohesion, which can make the viewing experience an exasperating one.

By the one-hour mark, the movie had almost lost me (though the early hour may have had something to do with it); soon afterward it started to grab me, and it held me as it picked up momentum and grew into an unholy Frankensteinian assemblage with hints of "The Matrix," a healthy dose of Darren Aronofsky's (commercially unsuccessful) "The Fountain," even a couple of cool nods to the cheesy '70s sci-fi classic "Soylent Green."

Warners may be able to sell the movie on the basis of stars like Tom Hanks, Halle Berry and Hugh Grant, but the film is bound to be divisive, and I fully expect some reviews to be savage. But for my money, any movie that finds me filling a page in my notebook with a litany of adjectives that includes messy, incomprehensible, glorious, silly, pompous, fun, wonderful, ludicrous and spectacular makes for three hours well spent – even if at times during those hours I wondered why I'd gotten up early.

Other Saturday debuts at Toronto included "End of Watch," David Ayer's tough and touching but not cynical LAPD movie that rests on the rapport between Jake Gyllenhaal and Michael Pena as longtime partners.

Also on the schedule was the unconventional "A Liar's Autobiography: The Untrue Story of Monty Python's Graham Chapman" (still above) an animated 3D film about the late comedian based on an "autobiography" in which Chapman told some facts, exaggerated others and made up some things entirely.

Directors Bill Jones, Ben Timlett and Jeff Simpson farmed out different section's of Chapman's book to 15 different animation companies, with styles all over the map and success sometimes as variable. The film is necessarily disjointed, occasionally very funny, and from what I know pretty true to the spirit of a guy who was always the unkempt (emotionally perhaps more than sartorially) and at times unreliable wild card of the group.

"The Perks of Being a Wallflower," meanwhile, is the rare high-school coming-of-age story that doesn't feel clichéd and calculating. Stephen Chbosky's adaptation of his own book is charming instead of cloying, with the help of a likeable and able trio of lead performers in Logan Lerman, Ezra Miller (so different from the last time he was in Toronto as the disturbing title character in "We Need to Talk About Kevin") and Emma Watson in her first substantial post-"Harry Potter" role.

I did walk out of the screening wondering about one plot point from the movie, and I overheard other people at a different TIFF screening discussing the same thing. The film is set in the early 1990s and its three leads are supposed to be smart kids with good musical taste. At one point they obsess over a song they hear once on the radio, and late in the film Lerman's character finally figures out what song it is.

This is treated as if it's some kind of revelation – but the song is David Bowie's "Heroes," the 1977 anthem that granted is more iconic now than it was in '91, but which would hardly be a mystery to kids who listened to bands like the Smiths.

That's nitpicking, but it bugged me. And while I'm picking nits, what's the deal with the hats and shirts for sale in the TIFF gift shop? They read "TIFF festival 2012" -- but since the last F in TIFF stands for festival, isn't it awfully redundant to sell merchandise that essentially read "Toronto International Film Festival festival?"

Just asking.