“Land of the Lost,” this week’s only big-budget release, brings an end to this summer’s streak of solid releases. It’s the immediate frontrunner in the race for worst summer movie.

Director Brad Silberling and his writers begin, of course, with the characters and premise of the campy ’70s TV show of the same title, but ultimately leave the memory of that series defiled.

Dr. Rick Marshall (Will Ferrell) has developed a theory that tachyons could be used to travel through time and space. However, his attempts to build his time-travel device fail. After being publicly disgraced by Matt Lauer (playing himself) and shunned by the scientific community for years, Marshall’s ambition is renewed by beautiful grad student Holly Cantrell (Anna Friel), the only person in the world who believes in Marshall’s theories.

Holly convinces Marshall to finish the device. When they try it out, Holly, Marshall and foul-mouthed, redneck survivalist Will Stanton (Danny McBride) are quickly transported to an alternate universe where dinosaurs prowl, ape-men speak and the half-lizard, half-human Sleestaks are trying to take over the world.

Their one ally in this strange land is Chaka (Jorma Taccone), an ape-man with an affinity for grabbing Holly’s breasts and making Marshall angry.

I wasn’t shocked that “Land of the Lost” is bad, I was shocked by how it was bad.

This movie, based on a kitschy family TV show, is one of the most vulgar PG-13 movies ever released. Anyone with fond, nostalgic memories of the show will feel violated by this movie. It’s more of an assault on childhood than an adventure comedy.

More than any other time I can think of, I feel morally obligated to warn parents to heed this movie’s rating. The profanity alone almost makes it deserving of an R-rating. At one point, Marshall mouths “F*** you” to Chaka. Virtually all other curse words are actually spoken multiple times.

This is not, in any way, a family movie.

Nor is it, like the 1995 “The Brady Bunch Movie,” a loving parody of the show made for adults who grew up with it. “Land of the Lost” shows very little affection for the original show.

Ferrell and company are aggressively, relentlessly aiming for the same audience as, say, “Superbad” or “Pineapple Express.” They are pandering to those who can legally purchase tickets but are still so immature they think pointless swearing and urine jokes are hilarious. But even those folks will be disappointed. “Land of the Lost” is every bit as crass and crude as most teen comedies these days, but it isn’t even funny on that level.

The jokes rarely work. Ferrell and McBride show very little chemistry and Friel is just the straight man. They each stick with their own schtick and it just doesn’t click.

The only funny moments come from a well-placed snippet from “A Chorus Line” and from, of all people, Matt Lauer. When a “Today” show anchor provides the high point of your movie, you’ve got problems.

I don’t go into a movie like “Land of the Lost” expecting quality writing or filmmaking. Enjoyable action sequences and playful references to a TV show whose very charm grew out of its own imperfections would have made for a fun couple of hours.

Instead, we are attacked by more scat jokes and sexual references than Sleestaks. Ugh.

Jeff Marker is a media studies professor at Gainesville State College.