Al Pacino, now 74, has nothing left to prove in the acting word. He has an Oscar, four Golden Globes, two Emmys and two Tony awards to his name and although he may not have another Serpico or Dog Day Afternoon on the cards, Pacino is continuing to turn in stellar performances. 

Al PacinoAl Pacino in 'Manglehorn'

He is the big name at the Venice Film Festival and anticipation has been high for two movies featuring the legendary actor, Barry Levinson's The Humbling and David Gordon Green's Manglehorn. 

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In the former - adapted from Philip Roth 2009's novel - Pacino plays Simon Axler, an ageing stage actor who has lost his spark. After embarrassing himself by diving into the orchestra pit during a Broadway production, he vows never to return to the stage and retreats to his Connecticut mansion to lock out the world. 

Manglehorn is a very different movie. Pacino plays a misanthropic locksmith who lives alone, with his cat. He is estranged from his son, a ruthless financier, and never got over the love of his life. 

BirdmanMichael Keaton and 'Birdman' opened the Venice Film Festival

" is entertaining, and its star Al Pacino often finds some very funny, rangy comic riffs," said Peter Bradshaw of The Humbling, "His bleary, bewildered performance is engaging, though you can never quite clear how deliberate his absentness is, or if, like Christopher Walken, he has boiled down a style and manner that will always be there no matter what he is saying and doing."

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"If Simon has, on some level, willed her into being, he's the one who ends up seeming the puppet on her strings, and when Pacino and Gerwig share the screen, they have a special chemistry that comes from two gifted actors pushing each other beyond their respective comfort zones," said Scott Foundas of Variety.

"Even acting doddery and looking ravaged (more like a rough Ian McShane than himself), Pacino is just too powerful in this part, too present as himself rather than his character, never actually humbled therefore," said David Sexton of the Evening Standard. 

This year's Venice Film Festival was opened by Alejandro G. Inarritu's Birdman, starring Michael Keaton.