So you may be wondering, as we are: Why did Ryan get A-listed over his arguably more talented costars? What gives him that extra spark when he can be, at times, little more than barely, pleasantly watchable. And when did this no-name pretty boy get on the track to becoming the Sexiest Man of the Year?

In order to properly assess the Ken Doll from up north’s rise to unlikely action hero fame, we have to go back to his somewhat humble beginnings. He’s been acting since he was a kid, most notably on Nickelodeon’s teen drama series “Hillside” — or, as it was called in the states, “Fifteen” — which was like “90210″ but minus the sex, drugs and valley girl accents:

As you can see, Ryan’s talent didn’t come from being a childhood thespian. He was good, but he didn’t pop off the screen. He was more, well, “adequate” is the word that comes to mind.

As recently as seven years ago, I remember being unable to distinguish the blandly handsome and pithy Reynolds from Michael Rosenbaum (who played Lex Luthor on “Smallville”), or Dane Cook. (Hey, they both were in that “Waiting” movie!) Ryan had cut out a niche for himself playing the smarmy “Saved by the Bell” types, like on ABC’s short-lived series “Two Guys, a Girl, and a Pizza Place,” or “Van Wilder,” a role that led to an odd reprise in “Harold and Kumar Go to White Castle.“ 

Though the role wasn’t supposed to be Van Wilder, per se, many people associated the cameo with Reynold’s only title character to date, mainly because Kal Penn’s first film happened to be the National Lampoon film.

Then in 2004, something funny happened. “Blade Trinity” came out, and even though it wasn’t even the best of the “Blade” franchise, something about Ryan’s embodiment of the vampire/vampire hunter Hannibal King struck a chord with audiences. Emphasis on the “body”: Reynold’s abs nearly stole the film. According to his interview in People for the 2010 Sexiest Man cover:

“My body naturally wants to look like Dick Van Dyke,” says the 6’2″ actor …. “When I stop training, I turn into a skin-colored whisper.”

Never before has an actor’s shirtless transformation so entranced audiences with his less-than-stellar performance. After “Trinity” Ryan went back to doing those passable rom-coms, like “Just Friends” and “Definitely, Maybe,” but it wasn’t till he was shirtless (and pants-less) with Sandra Bullock in “The Proposal” in 2009 that he once again garnered more attention. It was also the year that Reynold’s was announced to be getting his own “Deadpool” spin-off based on his other action role to date at the time: a toss-away character in “X-Men Origins: Wolverine,” whose quippy one-liners and flippant attitude regarding good and evil — along with some totally sweet guns — seemed to have been tailor-made for the actor.

And then there was his marriage to Scarlett Johansson. It’d be a mistake to underplay what this romance did for Ryan’s career; his previous public relationship announced as an engagement in 2004 (the year of “Blade Trinity) to Canadian singer Alanis Morissette, in a move that made us all go, “Who? Oh, that guy? Cool … glad she’s not with Dave Coulier anymore.” At the time of his first engagement, Ryan was still being referred to as “‘Van Wilder’ star.” Five years later, he and his wife were being named (independently) the sexiest people on earth.

When the couple separated late in 2010, I wondered if Ryan would just fade away. Now, about his former marriage, Reynolds will only say that the media wasn’t invited into his relationship, and “I’m a different person than I was six months ago.”  And that’s more than apparent: for maybe the first time in his career, Ryan is headlining a blockbuster summer action film. He’s more famous than his costars, and for more than just his good jawline, quick wit and jaw-dropping body. Ryan has finally obtained the unsinkable air of someone with “star power,” despite his seemingly lack of any, and it will be up to his next several career choices to see whether he can keep his momentum. And let’s hope his metabolism holds up too.

That said, movies like “Green Lantern” really aren’t aimed at girls, and you have to see Reynolds’ role as hotheaded flyboy Hal Jordan — who, no, isn’t the Green Lantern but the first human member of the intergalactic mind-over-matter strike force called the Green Lantern Corps — as an aspirational model for tween and teenage boys. Which could be viewed as depressing since, for all his gym-hardened abs, Hal is a dim and unfocused character who always looks as if he just thought of something he’s never thought of before, or else as if he’s wondering at which girl’s house he left the Camaro keys. I halfway wonder whether director Martin Campbell, an accomplished action-suspense stylist (“Casino Royale,” “The Mask of Zorro,” etc.), is using Reynolds’ lack of reactivity on purpose, to recall the lummox leading men of old-fashioned space operas.

For all the CGI action sequences and butt-rocking Dolby sound effects, in fact, “Green Lantern” is most satisfying when it sticks close to stodgy comic-book archetype (or myth, for that matter): A callow hero, granted inordinate power; a beautiful girl who doesn’t trust him; a mystical, universal order humans can barely comprehend; the unleashing of a great evil. This wouldn’t necessarily have been a worse movie if it had been made in Italy in 1977, with a bunch of people in tights and sets made of aluminum foil. As things end up, though, Campbell’s “Green Lantern” is much better entertainment than I was expecting. I enjoyed it more than “X-Men: First Class,” which has superior acting and production values but also feels rambling and pretentious. “Green Lantern” is purely a popcorn movie for 12-year-olds, who won’t be disappointed. (In fact, the PG-13 rating, while necessary for marketing reasons, feels forced; this movie doesn’t need or want its occasional cuss words or vague sexual references.)

I’m not sure what purpose plot summary serves with a movie like this: You either know it better than I do or you don’t care. Anyway, Hal is supposed to be a hot-stuff test pilot who’s a complete screw-up in every other area of his life, including his botched romance with Carol Ferris (Blake Lively), who looks good in her own test-pilot gear and in corporate-exec drag and in a leather jacket, without ever resembling a human being. Lively and Reynolds are well matched — they’re beautiful (in a narrow and technical sense of the word) and you can project onto them whatever you want. It’s startling, though, to realize there’s more than a decade of age difference between them; Reynolds is 34 and Lively 23, and can you even imagine a movie in which those numbers would be reversed, unless that was the whole point? (Insert rant about the ingrained institutional sexism of Hollywood here.)

Shortly after Hal has some kind of flashback-freakout and crashes an expensive jet fighter in the desert, a ball of green lightning scoops him off the street and takes him off to meet Abin Sur (Temuera Morrison), a dying alien Lanternoid who has crash-landed on Earth and recruited Hal as his successor. (OK, yeah, it’s the Power Ring, infused with the will of all the sentient beings in the universe, that does the choosing. Better?) Meanwhile, way out in deep space, the imperious leader of the Green Lantern Corps, purple-skinned Sinestro (Mark Strong), has a big problem to face. Some kind of ancient Sauron-Satan-Cthulhu entity called the Parallax, which looks like a giant Rastafarian hairdo surrounding a bulbous Dracula head, has escaped from its prison on the Lost Planet of Whatever and has embarked on a campaign to eat the universe.

I kid, but the Parallax is one of the best things about “Green Lantern,” an amorphous, soul-sucking and profoundly evil CGI beast with more personality than either of the human leads. Also terrific is Peter Sarsgaard as a wormy, balding scientist named Hector Hammond, who’s brought into a secret government facility to examine the corpse of Abin Sur, only to be infected by Parallax fear-juice or something and turned into a cackling mutant toady of doom. I’ve always enjoyed Sarsgaard’s acting, while also feeling that at every moment he’s asking himself, “Now, what would John Malkovich do here? I’m going to take that and dial it up a notch.” Fortunately, that’s exactly the right approach for this character.

So Hal’s got to be tested by the Lantern Corps on their distant planet of rocky outcroppings and stony pillars, where a posse of Yoda-like overlords called the Guardians manage all of creation. He’s got to fail and go back to Earth in disgrace and battle Hector and the Parallax and learn some life lessons and get the girl and set up a sequel, the end. (And please do not accuse me of “spoiling” anything with that sentence; what the Sam Hill did you think was going to happen?) Along the way, I think Campbell gets bored with the formula and sticks in some undertones that aren’t exactly in the script, which is one of those Hollywood mash-ups that results in a screenwriting credit containing both ampersands and “ands.” I mean, Sinestro looks like a combination of Hitler and Mephistopheles on purpose, and there’s something more than a little Nurembergian about the whole business with the Guardians and the Lantern Corps and the power of the universal will, and you almost wonder whether the Parallax has a nihilistic, Lars von Trier point to make about destroying all this boringness and starting over. John Milton faced the same problem when he tackled this material too.