Let's get the obvious points of comparison out of the way first: "Iron Man 3" is on a par with the original, way better than the lame "Iron Man 2" but nowhere near as good as last summer's "The Avengers," Joss Whedon's gold standard take on Marvel Comic's greatest superhero team.

The latest in the "Iron Man" franchise won't insult your intelligence, although it doesn't exude the smarts of the best comic book-based flicks. It has some neat action set pieces, a very sharp and self-aware performance by star Robert Downey Jr. (almost a given now with Downey) and a lively turn by Ben Kingsley as the villainous Mandarin. The film has notable flaws, but they never rise to the level of becoming fatal.

In other words, it's decent popcorn entertainment -- just fine for the summertime, but nothing more than that.

Fans of the Iron Man comic books will recognize the storyline that director/writer Shane Black ("Lethal Weapon") and his co-writer Drew Pearce (the upcoming "Pacific Rim") draw on for their script. "Extremis" was a six-book, 2005-06 arc that is widely considered one of the best in the character's long history. Considerable liberties have been taken, but many of the basics are there.

"Iron Man 3" takes place sometime after the "Avengers" throwdown with Loki in New York City, with Tony Stark (Downey) suffering from something close to post-traumatic stress. He's with his lover/long-time assistant, Pepper Potts (Paltrow), but he spends most of his time tinkering with new armored suits while she runs Stark Industries.

In the background, the Mandarin -- a bad guy from the earliest Iron Man comics -- is wreaking havoc around the world with a series of attacks. (Kingsley plays him, delightfully, as a cross between an Afghan warlord and a fire-and-brimstone Southern preacher.) Since things are never quite as simple as they seem, two figures from Stark's past -- brilliant inventor Aldrich Killian (Guy Pearce) and scientist/former lover Maya Hansen (Rebecca Hall) -- pop up unexpectedly. (He's the founder of Advanced Idea Mechanics aka A.I.M., a reference that will trigger an "uh, oh" from devoted comic geeks.)

When the Mandarin launches an attack that nearly kills Stark's friend and security chief Happy Hogan (Jon Favreau, director of the first two films), the battle lines are drawn. The terrorist launches a spectacular full-on helicopter assault on Stark's lavish Malibu home that nearly kills our hero and Potts. But Stark survives and is soon off on a cross-country chase that eventually involves an experimental miracle drug called Extremis, powerful and fiery super soldiers, an attack on Air Force One and a final showdown on the Miami waterfront.

The story should work, especially given an engaging cast. But it doesn't, and most of the flaws can be traced to Black.

Don Cheadle as Iron Patriot in &quot;Iron Man 3&quot;Zade Rosenthal/Marvel Studios
Don Cheadle as Iron Patriot in "Iron Man 3" Zade Rosenthal/Marvel Studios ( Zade Rosenthal )

A few director-writers,, such as Whedon and Christopher Nolan ("Dark Knight"), are comfortable with the conventions of the superhero world. But Black isn't one of them, and it shows. He does craft some strong individual scenes and a couple of neat twists, but the film is too jokey, with Black launching a shotgun blast of self-aware humor. There are some hits, but too many misses.

At times, "Iron Man 3" strays way too close in tone to Black's "Lethal Weapon," as if Mel Gibson's Martin Riggs has suddenly taken over the armored suit.

Still, there's enough to the film that there is zero chance people won't line up to see it. For that, Marvel should really be grateful to the cast, particularly Downey. This may be the last "Iron Man" for the actor -- at least as a solo adventure. (He definitely will suit up for "Avengers 2.") And the film does have a certain endgame feel to it.

If that's the case, it's too bad. Downey has been really good to the suit, turning Iron Man/Stark into a most intriguing and enjoyable character.


** 1/2
Rating: PG-13 (for comic book violence and action)
Cast: Robert Downey Jr., Gwyneth Paltrow, Ben Kingsley and Don Cheadle
Director: Shane Black
Running time: 2 hours, 15 minutes