To explain the ultimate source, and the lasting popularity, of Superman would take Carl Jung, “The Golden Bough,” and, quite possibly, Zane Grey. What we do know is that, since the Man of Steel’s initial appearance in June 1938’s “Action Comics,” he, like all the gods, devils, and myths of mankind’s collective unconsciousness, has changed along with the times in which he finds himself imagined. With “Superman Returns,” directed by Bryan Singer, he is still evolving.

If we start, as we should, at the very beginning, 1938’s man from Krypton was a “champion of the oppressed,” the New Deal in a red cape, tearing down slums, taking out irresponsible mine owners, and, for all I know, campaigning for higher tax rates. By the time of Max Fleischer’s glorious animations of the early 1940s, at their best still the finest representations of the Superman who fell to Earth, the plot-lines looked more like conventional science fiction, with our hero fending off the machines, monsters, and cackling villains we have all come to expect. There was a clear subtext too. Memories of the 1939 World Fair’s re assuring “world of tomorrow” had been displaced by wartime’s Frankenstein technology, and Superman became our ally against science gone mad, bad, or otherwise abused, a role he still plays.

In the 1950s, George Reeves was a Superman for the Eisenhower years, an extraterrestrial Ward Cleaver, invincible even beyond the confines of a fortress of domesticity. His mysterious death (suicide, with added murder rumors) at the end of that decade was, somehow, a suitable way to usher in a more disenchanted era, a time when the Man of Steel ran the risk of being seen as the Man of Corn, as square as the last boy scout, Clark Kent himself.

This must explain why when Superman returned to the big screen in 1978, the director, Richard Donner, felt that this was no longer a story that could be told with a straight face. Fortunately the leaden camp, heavy irony, and witless buffoonery that weighed down both that movie and its immediate successor were thoroughly subverted by the decency, kindness, and strength conveyed by Christopher Reeve in a remarkable performance that, despite a good try by Brandon Routh in “Superman Returns,” remains definitive.

Even Reeve could do little to save the slapstick-scarred “Superman III” and the moth-eaten “Superman IV,” the latter a movie that appeared to see Superman return to his lefty roots with an attack on nuclear weapons, not just the bad ones belonging to those pesky communists. Those films have, mercifully, been written out of history. Instead, “Superman Returns” is a sequel of sorts, a “spiritual descendant,” to “Superman: The Movie” (to which Mr. Singer’s plot owes a great debt) and “Superman II.”

But while the final decade or so of the last century saw enough twists and turns in the comic-book version of the saga to drive a continuity nerd to drool, it took the feelings of melancholy and danger that enveloped this nation in the wake of September 11, 2001, to create an audience for a sweet, straightforward, and oddly moving account of the young Clark’s life in television’s “Smallville.” At least in its early seasons, this series played on that nostalgic American heartland ideal that has always had so important a part in the appeal of the Superman story (and was one of the few redeeming features of “Superman III”). In a way, the sense of an imperiled Arcadia conveyed by “Smallville” was as emblematic of those troubled, troubling times as the flags then on sad, proud display on homes all across the country, including, naturally, that of Jonathan and Martha Kent.

With the exception of Eva Marie Saint’s touching performance as Ma Kent in “Superman Returns,” Mr. Singer makes little effort to play to this aspect of the saga, but the tone of “Smallville” must have had some influence on the director’s decision to take his subject matter more seriously than his predecessors. While Kevin Spacey’s Luthor is partly (and regrettably) played for laughs, his typically sly performance is an immense improvement on the imbecile clowning that defined Gene Hackman’s Lex. For the rest, with the disastrous exception of Parker Posey’s almost unwatchable Kitty Kowalski, the comedy is, thankfully, played down.

And then there’s Lois Lane. In the five years that Superman has been away searching for what’s left of his home planet (not a lot), Lois has acquired a fiance, a Pulitzer for her article on, oh dear, “Why the World Doesn’t Need Superman,” and, hmmm, a 5-year-old son. Adding to her difficulties, she’s played by Kate Bosworth, who is both too young and, despite a brunette hairdo, too blonde to be believable as spiky, dark Lois: Her inner Sandra Dee just keeps shining through. For a far more convincing Lane, try Teri Hatcher (Lois before Wisteria) in the counterfeit “Moonlighting” better known as “Lois & Clark” (1993-97), a wisp of a show for a frivolous time, where Dean Cain’s Superman was notable mainly as the Man of Snark.

Needless to say, when Superman returns so does his complicated relationship with Lois: there’s nothing new about that. What is different about Mr. Singer’s movie is the way in which it is a spiritual descendant of the earlier movies, in more ways than one. When, in “Superman III,” Clark dances with Lana Lang to the dulcet doo-wop of “Earth Angel,” it’s a clever joke. It’s an indication of the way in which “Superman Returns” reflects today’s more religious age that, in this latest chapter of the epic, the title of that old tune could be an almost literal description of who or what Mr. Singer’s version of Superman is meant to be.

As Superman’s real father (played by recycled footage of Marlon Brando from the first movie) explains, humans “only lack the light to show the way. … I have sent them you … my only son,” a clear reference to You Know Who, a recurrent theme of Mr. Singer’s film that is underpinned, in one instance, by a lovely sequence of Superman ascending into the heavens (the special effects in “Superman Returns” are first-rate) and looking protectively, and a little sadly, down upon our discordant planet, a gorgeous guardian angel carved not out of cathedral stone, but the filmmaker’s skill and the power of our own dreams. In her disloyal Pulitzer essay, Lois wrote that mankind has no need for a savior. By the end of “Superman Returns,” she has, needless to say, discovered how wrong she was.

But even if this movie sometimes seems to have the length of a sermon (it goes on a little too long), its borrowings from myth and religion are never preachy – they merely throw additional allegory into what is already a potent, much loved legend. And when, at the end of the screening, the audience began to cheer, they were not just cheering Mr. Singer’s fine film, but the legend itself, made up of their memories, their nostalgia, the stories they grew up with, the well-thumbed comic books, the courage of Reeve, that heartland ideal, and so, so much more, not least the fact that, at the conclusion of this movie, Superman promises that he’ll “always” be around.

And, as Clark Kent would say, that’s just swell.