I like it when children’s movies have plots that involve events that would be very grave if they happened in regular movies, but because they’re aimed at kids, the seriousness has to be glossed over. For example, here is “C.H.O.M.P.S.,” a chokingly cute comedy from 1979 that is set in an unnamed city during a shocking crime wave. There has been a rash of burglaries so extensive and unstoppable that it’s the only story on the TV news. “Not one of us is safe from these hoodlums who are invading our homes!” says the anchorman, with far less panic and terror in his voice than there ought to be if what he’s saying is true.

Home invasions? No one is safe?? In a movie for grown-ups, the response to this would be anger at the police for failing to their job, followed by paranoia, vigilantism, and eventually bloodshed. Charles Bronson would probably be involved. In “C.H.O.M.P.S.,” everyone’s pretty laid-back about the whole “our city is overrun with crime” thing, and a dopey guy invents an adorable robot watchdog! It’s the Canine Home Protection System, or C.H.O.M.P.S.! (Certain grammatical liberties have been taken.)

Our hero is Brian Foster (Wesley Eure, the boy from “Land of the Lost”). He works for Norton Security Systems, a burglar alarm company that’s been taking a hit lately because evidently its equipment is 1) used by every home in the city and 2) very easy to disable. Brian’s girlfriend, Casey (Valerie Bertinelli, the hot girl from “One Day at a Time”), is the daughter of his boss, Mr. Norton (Conrad Bain, the dad from “Diff’rent Strokes”). In 1979, seeing this movie was just like watching TV.

Anyway, Brian has a new invention that’s going to change everything. It’s the robot dog I mentioned 104 words ago. Brian isn’t just a security systems engineer who’s not very good at his job, he’s also a robotics engineer who’s brilliant at it! He has designed C.H.O.M.P.S. to look just like his real dog, Rascal, a cute mongrel of the Benji genre.

But before we get to C.H.O.M.P.S. the robot burglar alarm dog, let’s brainstorm for a minute on the features we’d expect a robot burglar alarm dog to have. Remember, for the product to be useful and worth making a movie about, it needs to be at least as good at preventing burglaries as a regular burglar alarm or a real watchdog. If it isn’t, it’s a huge waste of our time.

So let’s see. I’m going to guess that C.H.O.M.P.S. has supersonic hearing to detect prowlers, and that when it positively identifies a threat, it notifies the police via radio waves, or whatever they had in 1979. And obviously, with a name like C.H.O.M.P.S., it has a powerful bite that can hold a captured burglar in place till the cops arrive. That’s the best of both worlds: an alarm system to detect intruders, and a watchdog that can’t be bribed with steak.

Ah, interesting! I see Brian has gone a different route! His C.H.O.M.P.S. is nothing like that. It has super strength and x-ray vision, which are useful. But when it sees that burglars are lurking outside in the bushes, it smashes through the nearest window or wall to pursue them, which strikes me as unnecessarily melodramatic, not to mention expensive. The robot dog never bites anyone, either, nor is it said to possess that ability. It detains suspects by chasing them on foot all over town until the chaos gets somebody’s attention, or until the crooks fall into a dumpster or experience some other comical form of incapacitation. Again, at no point does C.H.O.M.P.S. bite anyone. It never even occurs to anyone that a robot dog might bite someone. After a dozen or so instances where C.H.O.M.P.S. could have ended a pursuit by sinking its teeth into the suspect’s leg and instead it dragged a parked car into the villain’s path (for example), I began to wonder if the people who made the movie were even aware that “biting” is something dogs do.

But they must have known. They named the movie “C.H.O.M.P.S.”

Another thing C.H.O.M.P.S. can do is follow voice commands. But since it’s a very high-tech robot, you have to say the code number that corresponds to the command. C.H.O.M.P.S. only responds to numbers. “Thirty-three!” you might say to C.H.O.M.P.S., and it will jump in the air. Why can’t you just say “Jump!”? Because it’s a robot, so it only understands numbers. Learn some science, dummy.

The obvious problem with this system is that if you happen to say a number in front of C.H.O.M.P.S. that is also one of his commands, he will do it, even if you weren’t talking to him. We learn this when Brian shows C.H.O.M.P.S. to Mr. Norton and Mr. Norton says, “I’ve seen your dog one hundred times!,” and C.H.O.M.P.S. karate kicks Mr. Norton in the chest because that’s what “one hundred” means. I don’t know why C.H.O.M.P.S. is programmed to attack the person who says the number, though, or why it would ever need to karate kick anyone anyway.

Every scene in “C.H.O.M.P.S.” is about one of these three things:

– Brian has C.H.O.M.P.S. demonstrate its abilities for someone, but not before the person says, “THAT’S your new security system? Is this some kind of joke?” or words to that effect. Often they will go back and forth for a couple minutes, with the other person getting exasperated while Brian remains smug. “THAT’S the security system?” “Yep.” “You must be joking.” “Nope!” “But it’s only a dog!” “This is C.H.O.M.P.S.” “What does it do?” “What DOESN’T it do?” [ad infinitum]

– C.H.O.M.P.S. is called into action — either because of real burglars or as a demonstration — and destroys a lot of property in the process of apprehending the villain. The only things C.H.O.M.P.S. does that a real dog can’t do are things you wouldn’t want a real dog to do, like smash through walls. The thing you would want a watchdog to do (bite) is not within the movie’s realm of knowledge.

– Bumbling thieves hired by a rival businessman try to steal C.H.O.M.P.S. and/or the plans to make more robot dogs. These thieves are played by old-timey comedians Chuck McCann and Red Buttons, and the businessman is Jim Backus, aka Thurston Howell III. Just think how dumb a movie has to be for me to tell you it’s the dumbest thing any of these actors ever did, including the one who did 98 episodes of “Gilligan’s Island.”

One time C.H.O.M.P.S. gets captured by a regular ol’ dog catcher and put in the back of the van. Then the dog catcher happens to say the number 21, and C.H.O.M.P.S. breaks out of the cage and through van door. Write that down! “Twenty-one” means “escape from the animal control officer.” (Also note that C.H.O.M.P.S. will only escape if someone is there to tell him to do it.)

Another time, while demonstrating what C.H.O.M.P.S. can do, Brian says “twenty-one,” and C.H.O.M.P.S. chases the man who was role-playing the burglar. So “twenty-one” also means “chase that guy.”

In the climactic scene, Mr. Norton is showing C.H.O.M.P.S. to some tycoons who may be interested in a merger on the basis of this revolutionary new invention. To test the robot dog’s skills, they have six trucks parked in front of land mines, only one of which is active, and C.H.O.M.P.S. has to find the active one and move it before the truck runs it over. You know, like a burglar alarm.

But Mr. Norton took Rascal the real dog by mistake! Brian, Casey, and C.H.O.M.P.S. arrive just in time to save everybody some embarrassment and some getting blown up. “I had him programmed for watchdog!” Mr. Norton says, referring to the dog that he thinks is a robot. “Neutralizing the explosives should be a cinch!” We can add Mr. Norton to the list of people who don’t know what watchdogs do, but in the meantime, C.H.O.M.P.S. dashes out onto the test field, retrieves the explosive, and sets it in front of the nearby shack where rival businessman Jim Backus is hiding and spying. And how did C.H.O.M.P.S. know to do all these things? Because Brian said, “Twenty-one!”

To summarize, here are the things that saying “twenty-one” will make C.H.O.M.P.S. do: break out of a dog catcher’s van; pursue a fleeing criminal; use an explosive device to expose corporate espionage. To be fair, there aren’t very many different numbers in our language, so there’s bound to be some doubling up of voice commands.

Important final note: Brian’s neighbor has a dog whose thoughts we can hear. Seriously. He’s the only animal in the film with narrated thoughts. When he encounters a nice elderly lady on the sidewalk, the dog says, “Up your poop, granny.” There’s no reason for the aggression, and the phrasing is nonsensical, but I guess what do you expect from a dog? Later on, the old lady is looking for her own dog, and she says, in this very prim English voice, “Has anybody seen my Muffin?” And you hope someone will answer, “Not yet, but the night is still young,” but they don’t, because everything about this movie is a disappointment.