At some point in the timeline of the new Syfy series “Krypton,” the planet is going to explode and pretty much everybody is going to die.

Nonspoiler alert!

C’mon, who doesn’t know Superman’s backstory? You don’t have to be a comic-book geek to know that Kal-El/Clark Kent escaped Krypton just before that planet exploded, came to Earth and became a beacon of truth, justice and the American way.

Heck, you know that even if you’ve never opened the pages of a comic book.

“Krypton” is a prequel to all that, set 200 years before the planet exploded and centering on Superman’s grandfather Seg El (Cameron Cuffe).

ON TV • Krypton” debuts Wednesday, March 21, on Syfy — 8 p.m. on DirecTV and Dish; 11 p.m. on Comcast.

To be honest, Superman has never been my favorite superhero. I know people who violently disagree with me, but I find him … kind of boring.

He has a spectacular origin story. But a guy who’s invulnerable kind of kills the drama, leaving the writers to cook up plots that involve Kryptonite.

Zzzzzzzz …

But in “Krypton,” everybody is on a planet circling a red sun and nobody has superpowers.

It’s two centuries ago, and Krypton is grim, totalitarian and sectarian. The El family is ostracized. Seg-El meets time-traveling Adam Strange (Shaun Sipos), who tells him he must make sure that his grandson, Kal-El/Clark Kent/Superman, is born. Does he save Krypton or let it be destroyed to save his future grandson?

Seg-El loves Lyta Zod (Georgina Campbell) — the grandmother of General Zod. And Brainiac (Blake Ritson) plays into all of this.

We’re assured the outcome is not a foregone conclusion because of the time-travel element.

What that means is that the ending of our show history could be changed,” said executive producer David S. Goyer, “and what happens in this show could be very different than the sort of backstory that most people know.”

That’s cryptic. And it’s still hard to believe that they’re going to end up someplace where Superman doesn’t end up on Earth.

The first five episodes are grim, dark, great to look at and not overly engaging. It’s not a bad show, but “Krypton” doesn’t exactly blow us away.

The plan is to broaden the series. Eventually. Goyer said that the inclusion of Adam Strange “should tip you off that it’s not just going to be set on Krypton.”

(If you’re a comic-book geek, that is.)

He envisions the show as “kind of a gateway into the DC science-fiction universe. ... The Phantom Zone figures into this show, which means we can definitely go into other times and other planets eventually.”

If the show continues past its initial 10 episodes, that is.