It's easy to feel sorry for Philip K. Dick. At the time of his tragically early death in 1982, he had the repute of a hack writer. Even though he copped a Hugo for 1962's Best Novel - unsurprisingly, for The Man In The High Castle - he hadn't won the respect that (say) Isaac Asimov or Arthur C. Clarke had won.
When he passed away, his Do Androids Dream Of Electric Sheep? had been adapted into the now-classic movie Blade Runner. If only he had lived to see this:
A variety of popular films based on his works have been produced, including Blade Runner (1982), Total Recall (1990), A Scanner Darkly (2006), Minority Report (2002), Paycheck (2003), Next (2007), and The Adjustment Bureau (2011). In 2005, Time magazine named Ubik one of the hundred greatest English-language novels published since 1923. In 2007, Dick became the first science fiction writer to be included in The Library of America series.
(From Wikipedia.)
And now, his ghost can smile upon Amazon's full-series adaptation of The Man In The High Castle. Yet another hit to his credit :)
The Secret Adaptation
As quoted above, Wikipedia recognizes Blade Runner as the first adaptation of Mr. Dick's works. Thanks to Youtube, that status is arguably wrong. Allow me to present, courtesy of the Brits, the long-forgotten 1964 movie that qualifies as the first-ever adaptation of Mr. Dick's underrated genius. Unsurprisingly, this film is an adaptation of the same Man In The High Castle - or at least was inspired by it.
Thanks to Youtuber vichogonzalez15, you're about to watch It Happened Here: The Story of Hitler's England.
Admittedly, the plot is quite different from High Castle but there's a definite similarity in the slice-of-life element. Instead of focussing on an antique dealer, it focuses on the adventures of a nurse, Paulie: a woman who's part of an evacuation to London. She's initially sympathetic to the Nazi occupation government, though this is clearly dramatic irony. More than half-way through the movie, her opinion starts to change through the civil procedure of asking untoward questions. :) Her disillusionment is reinforced by further slice-of-life experiences.
The opening scenes, which start after the all-British habit of putting the credits in front - makes it clear that we're watching an alternate-history war movie. Done on a low budget, it's clearly influenced by the huge crop of WW2 war movies. Instead of going all-in and projecting a future world controlled by the Axis powers, its plot imagines that the Nazis conquered and occupied Britain but not the United States. The British resistance gets a lot of help from the Seventh Fleet, imagined to be stationed around Ireland and attacking from the Irish Sea.
True to its WW2 vibe, the Nazis are portrayed early on as ruthless and bloodthirsty: shooting a whole group of disobedient civilians without mercy. A forced evacuation, which those murdered civilians defied, is present as stereotypically brutal. Interestingly, it's also portrayed as not efficient.
The first twenty minutes, especially the focus on women and children, are clearly inspired by the real-world dislocations endured by Londoners and others during the Battle of Britain. This is why the film has a female protagonist. The visible signs of Nazi occupation give it an eerie feel, at least to the folks who did go through the Battle of Britain who were watching it in '64. Naturally, one short scene shows a Nazi-imposed ghetto for Jewish people.
Interestingly, about twenty-five minutes in, the German occupiers are described as overlords who are lazy. The enveloping scene gives a glimpse of what a "better organized" Britain entails, as do the following scenes. Also of interest is the fact that the riot outside a bar shows ordinary Brits as folks who won't put up with being "better organized" if they're shoved around :)
Since I don't want to spoil the movie, I'll bow out with an evaluation. This movie's a period-piece two-star. If you like WW2 films, are a fan of the "Hitler Channel" or are a history buff, you'll find it to be enjoyable mind candy. It has a B-movie air, consistent with its modest budget, which gives it a raw unslick realism.
At the very least, it presents a period-piece look at filmmaker cover-ups in the "Inspired By..." department ;)