I recommend that all parents and grandparents of teens and young adults see “Due Date.” Why? Because is not only terrible, it’s gross.

Hollywood should be flooded with letters and e-mails from outraged adults who are not only offended by the movie, they are appalled that the movie industry would lure young people to see such crapola.

Professional pundits and movie reviewers who gave this picture an acceptable, yet high rating, should be fired from the syndications.

The story is about two fellows who stumble upon one another with their sets of problems. The character of Robert Downey Jr., is in a panic to travel cross country to get to his pregnant wife before she delivers. The slovenly character of Zach Galifianakis is a pot-head, struggling actor who offers Downey the ride. The rest is supposed to be a series of obstacles that the Director, Todd Phillips, intended to make us laugh. Instead, it made my wife and I want to throw up.

And we are not prudes by any stretch.

Much like teen movie crap, the virtues of smoking marijuana (ergo, using drugs) are glorified, mostly by sicko Zach. But the capper was when sicko Zach had to masturbate in the car he and Downey were sleeping in. That was as needed for the scene as vomiting on your popcorn.

As an actor, Zach and the industry is making big bucks, which is all that Hollywood cares about. Robert Downey Jr., is one of the fine actors in Hollywood today, but he lowers himself to the bottom for even appearing in a tasteless, script like “Due Date.”

It would be like Lawrence Olivier playing Conan The Barbarian, but replete with four-letter words that add nothing to the dialogue.

Parents should not make excuses: “Oh, well, that’s what kids like these days.” “Oh well, no harm.” “Oh well, I can’t do anything about it.”

Parents: Do something about it. Let your kids know that you care about the extremes in the entertainment world, that the incessant and idiotic use of “F” words, flatulence, regurgitation, and grappling with sex organs and body parts is a sad testament to where our society has fallen.

Show the kids you do care. Maybe that will make a difference with only 10 percent, but it’s ten percent better than zero.

Incidentally, this junk actor named Zach Galifianakis had the audacity to light up a marijuana joint on the Bill Maher Show last week, supposedly in the name of humor. The entire panel, including Maher laughed. In fact, the possession of marijuana is illegal in all states and in federal law, albeit the exclusion for medical marijuana in California. In essence, Zach thumbed his nose at the law, and Maher thought it was funny.

Bear in mind, I am an advocate in decriminalizing pot, but I’m also an advocate of obeying criminal laws while they are laws, especially on national television by entertainment role models.

Maher should have ordered “Cut!” and ushered the nutball off his set.

P.S. Yes. We walked out of the movie … just as the car was rocking to Zach’s disgusting hand job.

Click here: YouTube – Zach Galifiankis Marijuana-Smoking With Bill Maher!