After 10 years and a sometimes absurd number of plot twists, Tom Welling -- er, Clark Kent -- finally flew.

It was worth the wait. I would dare say that the two-hour finale of The CW’s “Smallville” was the best ending ever to a Superman-themed TV series.

“Smallville” debuted Oct. 16, 2001, a little more than a month after the 9/11 attacks. When it went off the air last week, “Smallville” became not only the longest-running Superman TV series ever, but the longest-running comic book-based series ever.

And the show wasn’t even about Superman. It was about Clark Kent. Despite being 24 when “Smallville” cast him as a very tall 15-year-old, Welling was Clark Kent for 10 years.

Sure, there were times when the character was a little whiny, complaining a little too much here and there about trying to fit in, whether or not a certain girl liked him, or even if his father really loved him.

Wait a minute -- isn’t that what all teenage boys go through? That was exactly the point. While some might argue that the journey from Clark Kent to Superman should have only taken five or six years, I don’t think that would have made sense. In the world of “Smallville,” Clark didn’t take up the “super” suit until he was 25 (Welling’s 34 now). Would viewers have accepted a 19-year-old Superman? I don’t think so.

“Smallville” definitely took liberties with the Clark/Superman mythos. Characters were introduced that were never in the comics, most notably Lex Luthor’s father, Lionel, and Clark’s best friend, Chloe Sullivan. Kryptonite affected humans, with the series falling on a poor crutch of Clark battling “meteor freaks of the week.” Later, the idea that a bunch of teenagers would be running around supposedly nearby Metropolis (a reimagining of the Twin Cities) was a bit of a stretch.

There were impossible plot twists that seemed more in line with an out-of-this-world 1950s or ’60s Superman comic. So, why did it work -- for 10 years, no less?

The success squarely goes to Welling. He has been quoted as saying he very deliberately did not read the comics or watch earlier shows or movies. Instead, he wanted to learn about becoming Superman at the same time Clark did.

It worked.

Even though he was nine years older than the part he was playing, Welling imbued young Clark Kent with the frustration, heartbreak, triumphs and joys you would expect of the journey “Smallville” intended to portray.

In Welling, Clark started as a boy discovering he’s an alien with super powers and became a man whose rock-solid principles made him a role model for everybody.

Clark’s relationships with his parents -- magnificently portrayed by Annette O’Toole and Jonathan Schneider -- was the foundation for those principles. His relationship with his biological father, Jor-El (actually an artificial intelligence simulacrum of him), while frustrating at times, turned out to be the tough love boot camp Clark needed to harness his powers responsibly.

His relationships with his friends, especially Chloe (Allison Mack); his future wife, Lois Lane (Erica Durance); and Oliver Queen/Green Arrow (Justin Hartley) amazingly provided the triple-threat of challenging, grounding and lifting him.

So, what of the finale? Spoiler alert, now...

The first hour focused on those relationships, capped off with Clark escorting his own bride down the aisle. Unfortunately, the ceremony’s interrupted and, well, I don’t want to give too much away.

In the background are two major challenges: the return of Lex Luthor and a global apocalypse courtesy of a cosmic villain named Darkseid.

Most of us grew up on Gene Hackman’s brilliantly campy portrayal of Luthor from 1970s movies. Michael Rosenbaum’s take on the character was equally, but dramatically, brilliant. Fans waited with baited breath to see if he would return (he left the show a few years ago) and -- with last minute writing changes -- Rosenbaum thankfully came back to close things out.

The second hour’s much more tightly focused on the pending doom of having Darkseid’s planet -- “Apokalips,” of course -- crashing toward Earth.

Two big things happen here. First, Darkseid, inhabiting Lex Luthor’s dead body, confronts Clark back at the Smallville farm he grew up on. While the confrontation is brief, it finally brings Clark’s powers to fullness and he flies for the first time. It’s a moment producers promised would only come in the last episode and they gave it every ounce of triumph I expected.

After taking Darkseid out, Clark rushes to his fortress (exactly like the one from the movies) and claims the Superman suit.

And then comes the biggest superfeat any live-action version of Superman has ever shown. Welling, now Superman, races over the skies of Metropolis and up to Apokolips which he then shoves. Out Of. Orbit. Wow!

Then there’s a seven-year jump with some beautiful touches, most notably a crisis that only Superman can deal with.

Welling’s Clark, with an assist from Durance’s Lois, heads up to the Daily Planet’s roof. There, he starts to take off his shirt, revealing the “S” symbol which closes in on the camera.

A great end to a great series about Clark Kent becoming the world’s greatest superhero.