It places the legendary scrapper in the context of his province's uneasy relationship with Canada, a union that officially began March 31, 1949, just over four months before his birth.
And it has some laughs along the way.
The National Film Board of Canada production spans Williams's earliest days as Newfoundland became Canada's newest province, to the tumult of his time as its ninth premier.
Williams, now 65, led the Progressive Conservative government from his landslide victory in 2003 until his blockbuster resignation in 2010. Cabinet ministers cried openly as he announced he was stepping down to refocus on private business ventures.
His popularity at home and across Canada soared during bombastic feuds with Ottawa over offshore oil earnings and equalization payments, culminating in his "Anything But Conservative" campaign against Prime Minister Stephen Harper in 2008.
Williams recalled Friday in an interview how he seethed during his first private meeting with Harper in October 2006. That's when he says the prime minister first bluntly backtracked on a written election vow to keep non-renewable energy resources out of the equalization funding formula.
"He took the gloves off first. And once he did, he was in the ring with the wrong guy."
The film documents his career as a criminal lawyer whose landmark wins include the battered wife syndrome as a defence for murder. It recounts his scramble in 1974 to raise $5,000 for a novel cable licence that he'd later turn into a fortune, selling Cable Atlantic in 2000 for more than $230 million.
His entrepreneurial flair was apparent even as a 19-year-old Rhodes scholar on his own for the first time at Keble College, Oxford in England. Williams recalls buying up legal robes that were tough to get in St. John's, then selling them back home for a tidy profit.
The film also uses a sketch from "This Hour Has 22 Minutes" to display his very Newfoundland ability to poke fun at his own flaws.
"Did you get the oil?" asks Newfoundland-born actor Gordon Pinsent, dressed in a black tux and holding a brandy snifter.
"Yes, Codfather," says Williams, seated beside comedian Mark Critch, another Newfoundlander.
"Did you get the lower Churchill?" Pinsent asks, referring to the Muskrat Falls hydro project in Labrador that was the former premier's last big deal in office.
"Did you throw a tantrum like a huge baby every time you didn't get your way?"
"Oh, yeah," Williams says with a smile.
Justin Simms, co-director of the film, said that infamous temper and stubborn streak are as integral to Williams as his intense work ethic and common touch.
"He probably wouldn't have achieved anything in his own life or as premier if he didn't have that quality."
If anyone steals the film, it's Teresita Galway Williams.
Still whip smart and a voracious reader at 89, she describes hollering from the stands when she'd watch young Danny, often the smallest player on the ice, drop the gloves in one hockey fight or another.
"Give it to him, Danny! Give it to him!"
She described how her son was adored and pretty much raised by a live-in nanny.
Teresita Williams was active as a Progressive Conservative volunteer and campaign manager while her husband, Tom, had a busy law practice.
Danny Williams was immersed from his earliest days in the twin influences of law and politics that would shape his life.
Today, the divorced father of four and grandfather of eight is philosophical about what his years in public life cost.
"Everybody who goes in pays a personal price but it's like anything," he said. "There has to be a balance. And hopefully, if you're fortunate enough to come out of it with a net gain, well then obviously it has been a win."
"Danny" is being screened across the province starting Monday.
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