It has Al Pacino and zombie girlfriends, Owen Wilson and Lars von Trier.

The 71st Venice Film Festival opens this week, bringing 11 days of high art and Hollywood glamour to the canal-crossed Italian city.

Twenty films are competing for the coveted Golden Lion prize — 19 of them world premieres — and several dozen more will jostle for the attention of critics and audiences at an event that mixes adventurous fare from international auteurs with mainstream movies seeking awards-season momentum.

Here are five films, trends and themes to watch for:

Birdman takes off

The festival — and the annual awards-season battle — kicks off Wednesday with the world premiere of Alejandro González Iñárritu​'s twisted comedy Birdman or (The Unexpected Virtue of Ignorance).

Anticipation is high for the film that promises to mix the bold, surrealism-tinged sensibility of Inarritu (Babel21 Grams) with inspired casting — former Batman star Michael Keaton plays a past-his-prime actor struggling to move beyond his best-known role as an iconic action hero. Zach Galifianakis, Edward Norton, Emma Stone and Naomi Watts also star.

Pacino double-take 

The revered veteran stars in two Venice films, handily screening on the same day and both infused with bittersweet longing.

Al Pacino in The Humbling

Al Pacino plays an aging actor having an affair with a younger woman in Barry Levinson's The Humbling, which makes its North American premiere at TIFF. (TIFF)

In David Gordon Green's Manglehorn, Pacino plays a small-town Texas locksmith pining over a long-lost love. In Barry Levinson's The Humbling — adapted from a Philip Roth novel — he's an aging actor having an affair with a younger woman, played by Greta Gerwig.

Also doing double duty are Ethan Hawke — starring in Andrew Niccol's drone-warfare drama Good Kill and Michael Almereyda's Shakespeare adaptation Cymbeline — and Charlotte Gainsbourg, who appears in Benoit Jacquot's romantic drama Three Hearts and von Trier's explicit Nymphomaniac.

America's uneasy conscience

Two competition entries look at issues troubling America's soul: war and economics.

Ethan Hawke in Good Kill

Ethan Hawke stars in Andrew Niccol's drone-warfare drama Good Kill with Mad Men's January Jones. The film heads to TIFF after making its world premiere in Venice. (TIFF)

In Gattaca director Niccol's Good Kill, Hawke plays a drone operator who grows disillusioned with remote warfare. Mad Men's January Jones also stars.

Ramin Bahrani's subprime mortgage drama 99 Homes stars Andrew Garfield (The Amazing Spider-Man) as an evicted man battling to get his home back. The cast also includes Michael Shannon and Laura Dern.

Unpredictable auteurs

Like its rival Cannes, the Venice film fest embraces actors and directors who are adventurous, unpredictable or down-right ornery. This year the festival is honouring James Franco, presenting the prolific American actor-director with the heroically titled Glory to the Filmmaker Prize.

Franco also will also premiere The Sound and the Fury, his second adaptation of a William Faulkner novel, at an out-of -competition festival screening. It has an impressive cast that includes Seth Rogen, Tim Blake Nelson and Jon Hamm. But the elliptical Faulkner is not easy to adapt and Franco's screen version of the Southern scribe's As I Lay Dying received a decidedly mixed response from critics.

Willem Dafoe in Pasolini

Willem Dafoe stars as the legendary Italian filmmaker, poet and novelist Pier Paolo Pasolini. (TIFF)

Other directors sure to provoke include Abel Ferrara, competing for the Golden Lion with Pasolini, a film about the outrageous life and violent death of Italian director Pier Paolo Pasolini, starring Willem Dafoe.

And Danish bad-boy von Trier is likely to bore and thrill in equal measure with the director's cut of his over-the-top sexual odyssey Nymphomaniac.

High arts meets Hollywood

It's the blend of big-name stars and cinematic surprises that makes festivals like Venice special.

New features are on tap from exciting international filmmakers, including Russian director Andrei Konchalovksy's The Postman's White Nights; Turkish-German director Fatih Akin's The Cut; Red Amnesia from China's Wang Xiaoshuai; and Tales by female Iranian director Rakhshan Bani-Etemad.

And if there were a prize for best title of the festival, it would certainly go to Swedish director Roy Andersson's A Pigeon Sat on a Branch Reflecting on Existence.

But it's not all art and existentialism. The schedule also includes Joe Dante's Burying the Ex — a zombie rom-com starring Anton Yelchin and Ashley Greene — and She's Funny That Way, a Peter Bogdanovich-directed Broadway comedy with Jennifer Aniston, Owen Wilson, Imogen Poots and Kathryn Hahn.