The great stars of Hollywood were, and maybe still are, our demigods. They have always existed on a magical plane, standing in for some cathartic fusion of who we are and who we want to be. They’re our idealized selves. But even all demigods aren’t created equal. In vintage Hollywood, there was a certain kind of movie star — Gary Cooper, Charlton Heston, and, of course, Kirk Douglas, who died Wednesday — that represented, in his look and his aura, a too-handsome-for-words stalwart “perfection,” one that spoke to the glory of America in the 20th century. These were actors who looked like they were put on earth to play Superman — and even without a cape, they played supermen. They were our larger-than-life heroes, our dream-god selves.

Kirk Douglas was the quintessence of that kind of star. When you hear his name, so crisp and ramrod strong (Kirk!), you think, at first, of how he looked: the jutting chin with a dimple that made it unlike all other jutting chins, the eyes that danced with charm but burned with intelligent rage, the swept-back coif and Olympian physique. One of the reasons Douglas is so defined by his role as the slave leader in “Spartacus” (apart from the fact that it’s simply a stupendous film) is that “Spartacus,” in its teeming immersive young-Stanley-Kubrick way, was the refined version of a cast-of-thousands sword-and-sandals spectacular — and Douglas looked like he was born to star in those movies. He could have played Spartacus, or the hero of “The Vikings,” for the rest of his career.

Very few movie stars have that golden-god quality, the one that leads from Kirk Douglas to Robert Redford to Brad Pitt, and you could say that for most of them it’s a strength but also, at times, a limitation. Humphrey Bogart could never have played an ancient strongman (at least not convincingly), but who cares? He didn’t have to. More tellingly, most of the stars who played ancient strongmen could never have played Rick in “Casablanca.” But Kirk Douglas could have! He had that moody festering spirit, that grand heartache, the glittering idealism that could turn, when thwarted, to cynicism.

To put it in terms of his sweet-spot era, the 1950s: Kirk Douglas had that Method Actor quality (in a way that stars like Gary Cooper never did). You first saw it in “Champion,” the 1949 ringside noir that elevated him to stardom, in which he plays a boxer who is asked to take a fall (Douglas shows you what a torment that would be), and in “The Bad and the Beautiful” (1952), which is nothing less than the greatest drama about classic Hollywood to ever come out of classic Hollywood. His unscrupulous movie producer, Jonathan Shields, will seduce and manipulate anyone to get what he wants, yet Douglas played the part with a hardboiled fusion of ruthlessness and romance. It was his chance to introduce what became the dark side of Douglas: fierce, clenched, driven by a passionate intensity. It was that side that made him complicated.

That he was born Issur Danielovitch, the son of Russian Jewish immigrants in upstate New York, may now be a famous fact (this was someone who titled his autobiography “The Ragman’s Son”), yet it’s always been my feeling that the primal image of what it means to be Jewish in America might have been cosmically different if everything about Hollywood were just as it was…with the sole exception of Kirk Douglas’s name change. In his heyday, the ’50s and early ’60s, Douglas’ fans, who had no idea of his true ethnicity, thought they were seeing the living epitome of American WASP might.

The line you hear about so many actors today (“He’s a character actor in a leading man’s body”) could have been invented for Kirk Douglas. But the thing is, he became such a powerful figure in Hollywood, producing as well as acting in movies, and helping to turn the tide on the Hollywood blacklist, that he never found himself trapped in a leading man’s body. He chose his projects with fearsome intuition and could act, brilliantly, even when he was playing The Square-Jawed Hero.

That’s what happened in “Paths of Glory” (1957), the timeless Kubrick drama of World War I that anyone who loves “1917” (and who hasn’t seen “Paths of Glory”) owes it to him or herself to experience. Douglas’s Colonel Dax is a commanding officer in the French Army who leads his men on a suicidal attack, then winds up defending three of the soldiers who’ve been court-martialed for cowardice. It’s not a happy-ending Hollywood war film (like “1917”). It’s a war movie that attacks the horror of the 20th century, which is what Douglas, in his powerful but wounded eloquence, gives voice to.

In “Paths of Glory” and “Spartacus,” Douglas acted from a place of highly observable anguish, and that was his quality as a star. He was the strongman who, at any moment, might be showing you his soul being torn apart. That’s why he was such a natural as Vincent van Gogh in “Lust for Life” (1956). It’s an old-fashioned and in many ways quite dated biopic, in that van Gogh, as an artist, now seems more contemporary than the movie itself. Yet Douglas throws himself into the role as if he were tossing himself overboard. He shows you a reckless side of himself and acts with a breathless devotion, a feat even more remarkable when you contrast it with the caustic nihilism of his newspaper reporter in Billy Wilder’s “Ace in the Hole” (1951), a drama that, seen now, shockingly anticipates our own era of cooked-up news and fake caring.

If you want to know why Douglas’ star faded so markedly in the mid-to-late-1960s, when he acted in plenty of movies (but few if any could be called memorable), it’s because he was a classic case of an Old Hollywood star trapped by the paradigm shift of the new era. He chased what looked like adventurous choices, such as Elia Kazan’s soap opera “The Arrangement” or “There Was a Crooked Man.” But he was too set in the mythology of his image to fuse with the New Hollywood. In 1978, Brian De Palma tapped Douglas’ gentle stoicisim in “The Fury,” but Douglas never enjoyed the moment of renaissance that John Wayne did. Maybe that’s because he was a producer, and because he had a son, Michael Douglas, who had become a major star in his own right. Kirk Douglas had already moved onto the realm of elder statesman, a role he remained in for decades. Even after his stroke, when he was 101 years old, peering out at the Golden Globes from his wheelchair, his eyes seemed ageless, cutting across the decades. He was fire and ice, he was noble and cynical, he was bad and beautiful: a movie star forever.