Stars of the silver screen descended upon the red carpet on the island of Lido for the opening night of the annual Venice International Film Festival on Wednesday.

"Birdman," this year's opening film and a contender for the Leone d'oro (Golden Lion) award, was well-received by critics, with the US magazine Variety describing the black comedy by the Mexicandirector Alejandro Gonzales Inarritu as "a triumph on every creative level."

Starring Michael Keaton, Inarritu's "Birdman" tells the story of a washed-up actor trying to make a comeback with a Broadway play after growing tired of his fictional on-screen role as the superhero title character.

Keaton had starred as Batman in the two Tim Burton films in 1989 and 1992.

Appearing alongside the 62-year-old is a stellar cast, including Edward Norton, Naomi Watts and Emma Stone, who, like Keaton, is no stranger to superheroes, having starred alongside Andrew Garfield in the two "Amazing Spider-Man" films.

Last year's opener, "Gravity", starring Sandra Bullock, went on to win seven Oscars despite going home empty-handed from Venice.

German presence

The listings for the festival, which runs until September 6, include two entries from the cinema veteran Al Pacino, in David Gordon Green's "Manglehorn" and Barry Levinson's "The Humbling".

Nominees for the Leone d'oro also include an entry from the director Fatih Akın, who previously won the 2004 Golden Bear award at the Berlin International Film Festival and cleaned up at the German Film Awards the same year with his drama "Gegen die Wand" (Head-On). This year's entry, "The Cut," depicts the Armenian genocide in the early 20th century.

German cinematic talent also makes an appearance in the Venice Classics section, which features the world premiere of the documentary "From Caligari to Hitler."

Missing Hollywood?

On this year's jury is the French film composer Alexandre Desplat, whose soundtracks include "The King's Speech," "Grand Budapest Hotel" and "Harry Potter and the Deathly Hallows."

He said he was looking for films that offer "new, original, strong and powerful insights."

"I think that's the purpose of cinema: to discover new worlds," he added.

Festival director Alberto Barbera has dismissed claims that this year's event is lacking in big Hollywood names, reaffirming the fact that the organizers' aim was to create a place to screen high-quality films that often risk falling unnoticed by the wayside.

"I have nothing against glamour, but it cannot be the only component in a festival," he said. "The idea is to explore cinema today in all its complexities."

Imprisioned directors

Italian President Giorgio Napolitano, a former cinema critic, attended Wednesday night's gala opening screening.

That was planned. Surprise guests at the event, however, were some 2,000 Venice city workers who were protesting against salary cuts as they blew whistles and carried placards, one of which compared the wage drops to a horror film.

Missing from this year's festival were the directors Mahnaz Mohammadi and Oleg Sentsov, who, respectively, have been imprisoned in Iran and Ukraine. Organizers have set two seats at the festival aside for the directors, and will ensure that they go unfilled.

ksb/mkg (Reuters, AP, AFP, dpa)