Plug and play.

One usually thinks of this phrase in reference to computer parts, but it works admirably well in reference to the various elements of “Good Boy!”

Plug in the earnest young boy. Plug in the serious parents who just don’t understand. Plug in the two stupid neighborhood bullies. Plug in the cute dogs whose personalities (of course) match their breeds. Plug in the requisite “fetch” and poop jokes.

-And then play.

While mostly harmless, “Good Boy!” is formulaic to the extreme. This Jim Henson Pictures production about a boy and his dog suffers from a lack of good jokes and an overdose of forced sentimentality. Oh, did I mention the dog comes from outer space? Can’t forget that.

In the movie, 12-year-old Owen (an adorable Liam Aiken) has been walking dogs all summer in hopes of receiving one of his own. His parents (an unusually staid Molly Shannon and Kevin Nealon) finally let him pick out a pooch, who just happens to be sent from — you’ll never guess — the Dog Star Sirius to report on dogs’ progress in their age-old mission to dominate humans.

Through a fluke, Owen gains the ability to speak to his new dog, named Hubble (voiced by Matthew Broderick), and together they prepare for the arrival of a Dog Star bigwig who has the power to remove all the canines from Earth.

The sad thing is, this movie, scripted and directed by John Hoffman, could have been really good. It’s not as though talking animals don’t work well in movies. Just look at “Babe,” a masterful satire that appealed to both small children and hardened adults. “E.T.” showed that alien visitors relating to human kids could be heartwarming. On paper, the premise of “Good Boy!” looks fine for a children’s movie.

Admittedly, “Good Boy!” is somewhat cute. Aiken basically carries the movie with his sincerity and a face that’s impossible to dislike. Plus, animal lovers may enjoy watching a crew of well-trained canines capering around for an hour-and-a-half.

However, Hoffman only bothered to stick in a few of the most obvious jokes, such as ones about “playing dead,” pup flatulence and poodle vanity, because, as everyone knows, all poodles are prissy females who love to admire their own beauty. In fact, all the dogs fit easy stereotypes, with the Great Dane being the most serious and commanding of them all.

These are not the sentiments of a jaded student too old to appreciate children’s cinematic fare. The mild gags of “Good Boy!” even sometimes fell flat sometimes with the kids in the audience. There has to be something missing when an 8-year-old doesn’t giggle.

Somewhere, somehow, someone forgot to plug the laughs into the formula for “Good Boy!”