Not quite as much fun as “Thor,” not nearly as bad as “Green Lantern,” “Captain America: The First Avenger” feels less like an exciting comic-book-hero movie than required reading for a course called “The Avengers,” arriving in theaters next summer.

Directed by Joe Johnston, this movie harkens back to the origin story of the original World War II-era Captain America – as opposed to the one who arrived with the birth of Marvel Comics in the early 1960s. But its bookend segments, which open and close the film, have the built-in answer as to how to move Cap into the 21st century for that “Avengers” movie, without concocting some extravagant time-travel tale.

As origin stories go, this one manages to get all the set-up out of the way in the first 40 minutes or so, in order to let this actually be a Captain America adventure, instead of yet another growing-into-his-powers story of a super-hero finally claiming his place in the universe and foiling the villain in the final reel.

The hero’s name is Steve Rogers and he’s played by Chris Evans who (through the miracle of computer wizardry) has his head grafted onto the body of a 98-pound weakling at the beginning of the film. It’s 1942 and scrawny Steve is dying to join the Army and go overseas to fight Hitler, like his pal Bucky Barnes (Sebastian Stan). But the Army keeps turning him down – until an insightful scientist, a German émigré named Abraham Erskine (Stanley Tucci), spots him for the potential hero he is.

Erskine picks Steve to be his first subject in a top-secret experiment to transform ordinary men into super-soldiers. It’s a serum he’s been developing since before he fled Hitler – and the Americans think it may be their best bet to defeat the Nazi’s own super-secret weapon, which is being developed by a vicious German bad guy named Schmidt.

Schmidt is also known as the Red Skull because he has, well, a red skull. It’s the byproduct of forcing Erskine to inject him with the then-imperfect super-soldier serum. (Try saying that five times fast.) The Red Skull is played by Hugo Weaving, whose accent makes him sound as though he is channeling Werner Herzog.

Erskine’s experiment is a success and Steve is turned into a he-man Nazi fighter: tall, buff and not-quite super-powered. But because a Nazi spy stole the last of the serum just after Steve was injected (you mean Erskine didn’t keep notes?), the Army is loathe to send him to fight; they’d rather study him to duplicate him. Instead, he’s conscripted to sell war bonds in a musical show, dressed in tights as “Captain America” – until he decides to take matters into his own hands while on a USO tour in Italy.

Frustrated at not being part of the action and aware that his pal Bucky is a German prisoner, Steve has himself dropped behind enemy lines, where he single-handedly frees Bucky and 400 other American prisoners, while helping destroy the Red Skull’s weapons factory. He gets industrialist Howard Stark (Dominic Cooper, as the father of Iron Man Tony Stark) to make him a tougher Captain America suit, with an indestructible shield that deflects both bullets and killer ray-gun beams, and works as a club and a boomerang, when necessary.

Director Joe Johnston helmed the unjustly maligned “The Rocketeer” 20 years ago; more recently, he was in charge of the dreadful “Wolfman” remake with Benicio del Toro. While “Captain America” echoes the gee-whiz biff-pow feel of “The Rocketeer,” the action itself consists mostly of one-sided fisticuffs and gun battles that barely excite.

While Johnston is able to give the fight scenes some dynamic scope, he can’t inject them with any real suspense or energy. Though the script introduces Sgt. Fury’s Howling Commandoes – minus Nick Fury – there’s little of the raucous give-and-take that made the Howling Commando comics as entertaining as they were. Meanwhile, the romantic tension between Evans and Hayley Atwell – as the scientist’s sidekick and Steve’s potential girlfriend – is tepid at best.

A word about Nick Fury: Fury, now the head of the secret spy organization SHIELD who has turned up at the end of the “Iron Man” movies in the person of Samuel L. Jackson, is something of a conundrum here. Yes, the comics explain how he can still be around running SHIELD after leading a World War II squadron (a little medication known as the Infinity Formula; hey, the guy is more than 100 years old).

Obviously it wouldn’t have made sense to put him in charge of the Howling Commandoes in this film because, just as obviously, there were no black officers commanding white units in WWII. Indeed, there was no integration at all – and it took a while before blacks were even allowed to see combat. Yet this film shows integrated units, including the Howling Commandoes, though without Nick Fury. (Yes, I know – Gabriel Jones (played here by Derek Luke) has always been a part of Fury’s squad – history be damned.) It all seems like someone was paying shoddy attention to the mythology.

But that’s the kind of thing that only critics care about, apparently. The rest of the audience will flock to “Captain America” this weekend and to “The Avengers” next summer because, well, making sense and telling a tale of substance are not high on the priority list of the comic-book movie fan, apparently.