As with most subjects, it was William Shakespeare who described the summer blockbuster most succinctly: "a tale / Told by an idiot, full of sound and fury, / Signifying nothing."

OK, fine; those lines from "Macbeth" are actually meant to describe life itself. But the Bard's words came to mind as soon as I watched the credits roll on "Man of Steel." And reflecting more generally on the billions of dollars of entertainment that Hollywood is offering audiences this summer, they seem particularly prescient.

"Man of Steel" serves as an epitome of what takes over theaters in the months we're most in need of their air-conditioned environs. Zack Snyder's 2006 battle epic "300" changed the way many action films are now made, and his reboot of the "Superman" saga has been one of the most anticipated films of the year. But "Man of Steel" is a completely conventional piece of work, adding nothing new to the genre of superhero action flicks that arrive like clockwork every summer. Sure, it gives us plenty of big things to look at: vehicles, explosions, the hero's biceps. But a few banal lines of dialogue here and there suggesting that all the death and destruction is being portrayed for a deeper purpose aren't enough to justify $225 million -- or nearly two and a half hours of your time.

This reboot is an origin story, and it starts right at the beginning: A woman is giving birth to the baby who will become the Man of Steel. It's the planet Krypton's first natural birth in centuries, the father, Jor-El (Russell Crowe), says, which makes the infant, Kal-El, the only Kryptonian not born to serve in a government-defined role. But the baby isn't long for Krypton. The scientist Jor-El sends him -- along with the "codex" of all possible Kryptonian DNA -- to Earth just before the planet implodes.

On screen
'Man of Steel'
» Rating: 1.5 out of 4 stars
» Starring: Henry Cavill, Amy Adams, Michael Shannon
» Director: Zack Snyder
» Rated: PG-13 for intense sequences of sci-fi violence, action and destruction, and for some language
» Running time: 143 minutes

A few other Kryptonians have survived, however: criminals sent into exile, like General Zod (Michael Shannon), a nasty military leader who launched an unsuccessful coup just before the planet fell apart. He's determined to find Kal-El and, along with him, the DNA to create a new Krypton.

Thank goodness the baby's spacecraft landed in the Midwest. He's adopted by Jonathan and Martha Kent (Kevin Costner and Diane Lane) and instilled with the kind of values that will keep him from becoming a megalomaniacal maniac who would use his powers for evil. Clark Kent's father insists the world isn't ready to meet an alien with super strength, even if he is an inveterate do-gooder. He instructs his son to keep his talents secret, even if it means letting innocent people die.

But the adult Clark (Henry Cavill) can't quite manage it, and the reporter Lois Lane (Amy Adams) is soon on his trail. And then Zod is, too, threatening to destroy humanity if Clark doesn't surrender -- or if humanity doesn't surrender to him.

It's a variation on the dilemma posed to passengers of two ferries in "The Dark Knight." "Knight" director Christopher Nolan helped develop the story for "Man of Steel," but his ideas, if any remained, are rendered into platitudes mouthed unconvincingly by various characters, as when the Kansas farmer Jonathan Kent tells his son he will one day challenge what it means to be human.

Much time was spent bulking up Cavill, and the effect certainly seems worth the effort. But perhaps some of that energy should have been put into the screenplay. When it's not boring -- I liked the fight in the air better when Clive Owen did it to the sounds of AC/DC in "Shoot 'Em Up" -- "Man of Steel" is either nonsensical or preposterous. (Or pointless, like the 3-D added in postproduction.) Jor-El talks a lot of bloodlines and insists Kryptonians be born free to pursue their own paths, not those assigned to them at birth. But he constantly demands that his son be the leader of an alien race that doesn't even know of his existence. No one can figure out what Jor-El did with the codex until one of the bad guys suddenly just realizes where it must be. A government scientist informs us the Kryptonians have begun "terraforming" Earth to suit themselves, which makes no sense.

Cavill does the best with what he's been given. He's mostly meant to look strong and serious, and he does. Shannon's work here is just embarrassing -- I expect a clip of him shouting, "NoooOOooooOoo!" to make it onto YouTube soon. Adams starts out a gutsy, daredevil reporter, only to spend the rest of the movie staring adoringly at Superman. The movie didn't need to be nearly two and a half hours, either. The ending is particularly ridiculous, with a series of lines that the screenwriters obviously liked but couldn't fit in anywhere else.

I call the character Superman, but this reboot tells us the symbol on his inexplicable costume isn't an "S" but the sign for "hope" on Krypton. But "Man of Steel" offers little hope that Hollywood will soon focus its vast resources on doing good.