Each year, millions of viewers worldwide tune in for Hollywood’s biggest night: the Academy Awards gala.

It’s an over-the-top celebration of cinema, with fans around the globe captivated by the films in contention, the glitzy celebrities attending or the annual parade of fabulous (and perhaps not so fabulous) fashions.

For the nominees, the Oscars represent a sleek and shiny finish line that comes after months of box office angst, kudos (or catcalls) from critics and what’s now a marathon movie-awards season.

By this point, front-runners have been declared (à la Daniel Day-Lewis in Lincoln) and then amended (as with early favourite Zero Dark Thirty fading in face of the more recently preferred Argo). Various storylines have tugged at our heartstrings, like the struggles to bring the young, wide-eyed, non-actor stars of films like War Witch and Buzkashi Boys to Hollywood to share in the red carpet spotlight.

CBC News highlights a few moments to watch out for during Sunday night's inevitably lengthy Oscar broadcast. Red carpet arrivals begin on host network ABC at 7 p.m. ET, with the main Academy Awards ceremony starting at 8:30 p.m. ET.

1. Funnyman or failure?

2013 Oscar host Seth MacFarlane is a multifaceted player in the entertainment world: creator of TV hit cartoon Family Guy, bizarre mind behind the raunchy puppet bromance Ted and Royal Albert Hall-worthy crooner of musical theatre standards. We’ve seen him host Saturday Night Live admirably (as well as a Comedy Central roast of Charlie Sheen), but being Oscar-night emcee is a tricky gig of a whole new magnitude. The job has tripped up noted late-night superstars like Jon Stewart and David Letterman, yet boosted the reps of gently corny Billy Crystal and triple-threat Hugh Jackman.

We understand if MacFarlane has major anxiety about his Oscar duties. Every aspect of his opening monologue will be dissected in detail, his performance throughout the night picked apart mercilessly and — just when we think it’s over — he’s to perform alongside big-voiced Broadway star Kristin Chenoweth in a broadcast-ending musical number. Oh, and did we mention he’s also a nominee (a best-song contender for co-writing the tune Everybody Needs a Best Friend from Ted)? It’s enough to unnerve any normal person.

2. Movie music

Oscar broadcast producers Craig Zadan and Neil Meron are veterans of TV, film and stage, but more importantly, they’re musical theatre buffs. So it didn’t come as a surprise that they’d put this year’s focus on cinematic music. One much-touted segment of the evening is a salute to movie musicals of the past decade, with Jennifer Hudson (Dreamgirls), Catherine Zeta-Jones (Chicago) and the stars of best-picture nominee Les Misérables (including Hugh Jackman, Anne Hathaway, Russell Crowe and Amanda Seyfried) to take part.

3. Standout singers

Oscar night is also shaping up to be a showcase of acclaimed female vocalists. Norah Jones will perform the nominated track Everybody Needs a Best Friend. Fellow best-song contender Adele will give the first-ever live performance of her James Bond tune Skyfall. British icon Shirley Bassey will continue the 007 theme during a special tribute to the 50-year-old superspy film franchise. And, in perhaps one of the evening’s most anticipated and carefully kept under wraps appearances, the incomparable Barbra Streisand returns to the Oscar stage to perform. "During the course of the show, at some point, Barbra Streisand is going to come on and do something really special and blow people away," producer Zadan told The Hollywood Reporter.

4. The Canuck connection

Viewers searching for Canadian content have several Oscar categories to keep an eye on. Montrealer Kim Nguyen sails into the Academy Awards on a wave of film festival kudos for his child soldier drama War Witch (also known by the name Rebelle). It’s the third consecutive Quebec film to represent Canada as an Oscar foreign-language film finalist.

Mychael Danna’s recent Golden Globes win and his special honour from the Palm Springs Film Festival have helped cast the Toronto composer as a frontrunner in Oscar’s best-score category for his work on Life of Pi. He also earned a second nomination for composing the track Pi’s Lullaby.

Meanwhile, Canadians are a serious force in the live-action short category. Montreal filmmaker Yan England is a contender for his late-life tribute Henry. Fellow Montrealer Ariel Nasr is a rival for the Afghan coming-of-age tale Buzkashi Boys, which he produced. A third Canadian is also a finalist in the category: Toronto-raised producer Mino Jarjoura for the Somali pirate drama Asad.

5. The age factor

Oscar’s best actress race typically highlights five acclaimed performances, but this year there’s a rare juxtaposition in the mix. Jennifer Lawrence (Silver Linings Playbook) and Jessica Chastain (Zero Dark Thirty) may be touted as the lead contenders, but don’t discount the two ladies representing either end of the age spectrum: Amour star and oldest-ever lead actress nominee Emmanuelle Riva, who celebrates her 86th birthday on Oscar night, and nine-year-old Beasts of the Southern Wild darling Quvenzhané Wallis, the academy’s youngest-ever nominee in the category. Rounding out the finalists is Naomi Watts (The Impossible).

6. Affleck’s revenge?

Nevermind that Ben Affleck’s Iran hostage thriller Argo is one of this year’s leading Oscar contenders, with its seven nominations — including in the expanded best-picture field.

That he was missing from the race for best director turned Affleck and Argo into the cause célèbre of the awards season. Leaving aside the Canadian controversy (like so much in Hollywood, the movie takes historical liberties for entertainment’s sake), Argo is a slickly made, fast-paced, smarter-than-average movie. Still, its utter dominance this season (including winning top film honours at the Golden Globesthe BAFTAs and from the Screen Actors Guild, the Producers Guild, the Directors Guild, the American Cinema Editors and the Writers Guild of America) has been somewhat startling.

Affleck’s already got an Oscar at home, having shared an original-screenplay win with buddy and Good Will Hunting co-scribe Matt Damon back in 1998. Still, if Argo ultimately captures the top Oscar — best picture — as is being predicted, it will likely prove the sweetest revenge and the ultimate finale to a surprising show biz story.