The world premiere of "Victoria & Abdul", Stephen Frears' big-screen adaptation of the true story of the elderly Queen Victoria's friendship with an Indian clerk, is set to be a highlight of the 74th edition of the world's oldest cinema festival.
The 2017 festival gets under way with Oscar-winning US director Alexander Payne's sci-fi comedy "Downsizing" in an opening slot that, in recent years, has been a trampoline to future international success for the films involved.
The beachside bash runs until September 9, when the winner of the Golden Lion for the best of the 21 films entered in the main competition, and a string of other prizes, will be announced.
Silver screen legends Redford, 81, and Fonda, 79, are due on the Lido, the sandbar island that hosts the festival, on Friday to receive lifetime achievement awards, before an out-of-competition showing of their latest film, "Our Souls at Night".
Produced by Redford for Netflix and directed by India's Ritesh Batra, the film sees the one-time sex symbols play elderly widowed neighbours pursuing a friendship that becomes increasingly intimate.
British director Frears is to be honoured on Sunday for his innovative contribution to cinema, ahead of the premiere of "Victoria & Abdul", in which Judi Dench stars opposite Bollywood actor Ali Fazal.
British director Stephen Frears will receive a lifetime achievement award at this year's Venice film festival.
File Photo: Justin Tallis/AFP.
The subject of much pre-release excitement, the film is billed as a wry look at issues of race, religion and power at a time when the British Empire was at its peak and India was its "Jewel in the Crown".
Coming at a time when Britain and India's post-Empire relationship is being recast by the former colony's economic growth, the film sees Frears return to the theme of royal comportment he addressed, to much acclaim, in "The Queen" (2006).
Dench, meanwhile, is portraying Victoria onscreen for a second time, 20 years after the release of John Madden's equally praised "Mrs Brown".
The likes of Matt Damon and Michelle Pfeiffer are also expected to be spotted hopping off and on gondolas during an industry gathering that has become an important launchpad for Oscar contenders.
"La La Land", which went on to collect five Academy awards including best director and best actress, took its first dance steps on the Lido last year, along with fellow Oscar winners "Arrival" and "Hacksaw Ridge".
Their success extended a remarkable four-year streak for festival director Alberto Barbera after Venice showcases helped propel "Gravity", "Birdman", and then "Spotlight" to success at the 2014, 2015 and 2016 Oscars, respectively.
"Gravity", "Birdman" and "La La Land" were all shown in the coveted opening slot that Payne's "Downsizing" occupies this year.
A sci-fi comedy, it stars Damon as a man who realises he would have a better life if he shrank, and Kirsten Wiig as his indecisive wife.
Thrillers and Thriller
"Downsizing" is one of seven US productions in the main competition. Others include the Clooney-directed "Suburbicon", Chinese artist Ai Weiwei's epic documentary on the global refugee crisis and "mother!" by "Black Swan" director Darren Aronofsky.
The latter is one of several thrillers vying for honours. With Jennifer Lawrence in a lead role, it tells the tale of a couple thrown into turmoil by uninvited guests.
Another spine-chiller features Ethan Hawke in Paul Schrader's "First Reformed", which turns around a dark secret harboured by members of a church who are tormented by the deaths of loved ones.
Britain's Martin McDonagh, best known for the 2008 black comedy "In Bruges", will also hope to have a jury chaired by Annette Bening on the edge of their seats.
His "Three Billboards Outside Ebbing, Missouri" stars Frances McDormand as a mother trying to get to the bottom of her daughter's unsolved murder. Damon also stars alongside Julianne Moore in "Suburbicon", a dark Coen brothers-scripted comedy dealing with the underbelly of violence in 1950s American suburbia.
More dark themes are explored in "The Exorcist" director William Friedkin's documentary about real-life exorcisms and in Netflix's first Italian original series "Suburra", which deals with gangster-politician links in Rome.
On a more upbeat tone, there will also be a new 3D version of the late Michael Jackson's "Thriller", accompanied by Jerry Kramer's 1983 documentary about the making of one of pop's most celebrated and influential videos.
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