MORE than a decade after Al Gore galvanised popular opinion on climate change in the strangely compelling documentary about his travelling slide show, he's back.
While the message hasn't changed, the former US Vice President's delivery has.
There are times, in the sequel to An Inconvenient Truth, when he appears bruised and battle weary.
"If I said there weren't times where this felt like a personal failure on my part, I'd be lying," he says in relation to the glacial pace of change.
At another point in An Inconvenient Sequel: Truth To Power, which focuses on the man as much as his message, the 69-year-old environmentalist acknowledges periods of deep despair.
The physical evidence of global warming is sobering - 14 of the hottest 15 years on record have occurred since 2001.
"The evening news has become like a nature hike through the Book Of Revelations," he observes, with dark humour.
In Greenland, Gore and a scientist walk over a melting ice cap, In Miami, the long-time climate activist inspects submerged streets.
The filmmakers also revisit a controversial prediction in the original film that a combination of sea-level rise and storm surge would flood the 9/11 memorial site, cutting to news footage of Hurricane Sandy doing exactly that in 2012.
Gore works overtime, however, to balance the shocking doomsday science with messages of hope and examples of practical optimism.
In one segment, he visits Georgetown, Texas, a city that is powered by 90 per cent renewable energy.
"This is the reddest city in the reddest county in Texas," the mayor, a conservative Republican, informs Gore before cheekily requesting a paired photo outside party HQ.
In the second half of the film, there's a narrative arc, of sorts, that plays out against the backdrop of the 2015 Paris climate conferences, where the filmmakers suggest Gore played a pivotal role in getting the hard-fought-for accord across the line. (The documentary was re-edited in the wake of US President Donald Trump's withdrawal from the Paris Agreement.)
As a piece of filmmaking, Truth To Power is not as focused as its predecessor, perhaps because the directors (Bonni Cohen and Jon Shenk) are a little star struck.
As a kind of coda to the original film, however, Truth to Power feels very timely.
And Gore's tenacity in the face of so many setbacks is hugely impressive. This is a man for whom the term indefatigable could have been coined.
An Inconvenient Sequel: Truth to Power
Stars: Al Gore
Directors: Bonni Cohen, Jon Shenk
Rating: 3.5 stars
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