“Mission: Impossible III” is the best two-hour long episode of “Alias” ever filmed without Jennifer Garner. Well, that’s not entirely true. The third installment of the “Mission: Impossible” franchise isn’t as smart as “Alias,” and it lacks the compelling characters and emotional engagement of the small-screen spy series. But whatever.

“Mission: Impossible III” is the best two-hour long episode of “Alias” ever filmed without Jennifer Garner. Well, that’s not entirely true. The third installment of the “Mission: Impossible” franchise isn’t as smart as “Alias,” and it lacks the compelling characters and emotional engagement of the small-screen spy series. But whatever.

“Mission: Impossible III” (hereafter referred to as “MI3”) and “Alias” are more alike than they are different. Let me count the ways. First and most obvious, “Alias” creator J.J. Abrams directed and co-wrote “MI3.” Abrams has a keen sense for what makes the spy-fi genre work on the small screen, and with “MI3,” he just makes everything bigger. The gun battles are louder, the explosions are huge, and the hand-to-hand combat is a little more harried. It’s sort of like a big chocolate layer cake of a movie, with the impossible missions that Ethan Hunt (Cruise) and his band of spies engage in as the actual cake, and the “emotional” moments between Hunt and his wife Julia (Michelle Monaghan) as the saccharine frosting.

But more specifically, “MI3” follows the general set-up of “Alias” to the letter. There’s a beautiful female spy in danger (Keri Russell, whom Abrams worked with on his first TV show, “Felicity”), a goofy tech-guy (“Shaun of the Dead” star Simon Pegg), an uber-cool villain (Philip Seymour Hoffman), and even an appearance by Greg Grunberg, a longtime Abrams collaborator who appeared regularly in “Alias.”

There are some differences, of course, but they’re not important. The plot of “MI3” follows that of most other spy flicks: a semi-retired agent, in this case, Ethan Hunt, is called back into the field to take down a particularly evil bad guy. Hunt gets sent on a chase for a device that amounts to an apocalyptic MacGuffin called the “Rabbit’s Foot.” Hunt’s motivation: his wife Julia has been kidnapped by international arms dealer Owen Davian (Hoffman), a laid-back sociopath who wants the “Rabbit’s Foot” in exchange for Julia. All is not as it seems, of course, and, much like “Alias,” “24,” and every other spy drama in the last decade have taught us, Hunt’s friends in the IMF (the Impossible Missions Force, not to be confused with the International Monetary Fund) are not as friendly as they seem. You’d think they’d start doing more intense background checks.

Originality aside, “MI3” is still a lot of fun. Abrams can construct an action sequence with the best of them, and there’s plenty of banter between characters to keep things light while the bullets fly. If only “MI3” were all action scenes, though. For whatever reason, there’s lots of what are supposed to be touching moments between Hunt and Julia, but those scenes just never click. Is it because Cruise has spent so much time off-screen jumping on couches and talking about eating placentas that his real-life persona has gotten too big? Or has he just gotten lazy as an actor? Maybe it’s both. Cruise doesn’t have much credibility anymore, and the difference is especially glaring when he’s sharing the screen with someone like Hoffman. In “MI3,” Hoffman is so casually evil, so relaxed and confident in his villainy, that he makes Cruise’s heroic emoting seem almost embarassing.

But we’re not going to “MI3” for the performances, are we? Of course not. If you want sexy spies, surprise plot twists and lots of ass kicking, you can go out and see “MI3” or stay at home and watch “Alias.” Either way, you’ll get what you want.