It isn’t just Spider-Man who loses his way in the third and last installment. It’s the movie.

A superhero movie should have (1) cool special effects, (2) a great villain, (3) thrilling action scenes, and (4) just enough plot to keep things moving without getting in the way of (1), (2), or (3). It is in this last category that this movie goes wrong.

Too many villains. Too many plots. Too many girlfriends. Too many people who died in earlier installments coming back for a last bow. Too many NOW-you-tell-me! revelations with way too many if-only-I-had-known ramifications. And way too many tears. Boy, is there a lot of crying in this movie. Is this Spider-Man or “Days of Our Lives?”

Peter Parker (Tobey Maguire) starts out with everything going his way, which means that we will have to see it all taken away from him so that he can get it back again. As the movie begins, Spider-Man is universally beloved as a hero and he is happy at school and at work. Best of all, MJ (Kirsten Dunst) is in a show that is opening on Broadway and she and Peter are finally a couple and he is thinking about proposing to her.

Then things get complicated. Peter’s one-time best friend Harry has taken up his father’s old Goblin persona and is coming after Peter to avenge his father’s death. Escaped con Flint Marco (Thomas Haden Church) desperately needs money for his sick daughter. Running away from the police, he doesn’t notice that “Keep Out” sign on the “particle physics test facility.” Uh-oh. Some sort of super-powering mutation rays are about to turn him into the Sandman. And Eddie Brock, Jr. (Topher Grace) wants Peter’s newspaper photography job and he thinks Peter wants his girl (Bryce Dallas Howard as Gwen Stacy, daughter of the police commissioner).

Wait, there’s more. Things start going badly between Peter and MJ, especially after he rescues Gwen and gets a grateful kiss. And there’s a mysterious outer-space scritchy sort of thing that looks like a cross beween magnetic tape and spaghetti. It latches onto Peter and seems to have the same effect as steroids — performance enhancement plus rage enhancement. Somehow it also affects his hair, which starts to hang in his eyes. It is supposed to make him look rakishly dangerous, but it just makes him look like the lead in a road company production of “Sprintime for Hitler.” And it makes him wanna dance so that he walks down the street like John Travolta in Saturday Night Fever.

Yes, there’s a dance number. Wait, there’s more. It turns out that the man they thought killed Peter’s Uncle Ben was just an accomplice. The real killer is still at large. At least two characters have some very important jewelry of great sentimental value that almost gets lost for good. And for no reason whatsoever, a character decides to divulge some information that if he had just come clean two movies sooner would have saved us all a lot of trouble. And we have to pause a couple of times for comic bits from the landlord’s daughter, Spider-man creator Stan Lee, and from Evil Dead’s Bruce Campbell, and one unnecessary line each from two kids who have the same last name as the director and his co-screenwriter brother. And don’t forget there’s always time for a slam at critics.

It’s a mess. There are some cool effects and some affecting moments. But they are buried under too much clutter, too much plot, too much everything. Hollywood has done more to damage Spider-Man than any of his onscreen foes.

Parents should know that there is a lot of action-style peril and violence, and characters are injured and killed. A character drinks to deal with unhappiness. A strength of the movie is a rare portrayal of a character who prays.

Families who see this movie should talk about why Peter did not know what was going on with MJ. Which of the villains in the three movies was the best and why?

Families who enjoy this movie will also enjoy Spider-Man and Spider-Man 2. They will also enjoy reading the original stories in Amazing Spider-Man Omnibus, Vol. 1.

NOTE: This movie has extremely graphic, grisly, violent, and disgusting images, situations, and characters. It is not appropriate for anyone under 18 or for many adults. The positive rating is only for its intended audience, fans of this genre.

Famously violent but critically acclaimed film-makers Quentin Tarantino and Robert Rodriguez are fans of “grindhouse” movies. A grindhouse was a theater specializing in exploitation films — movies made with no artistic pretense or aspiration, with more attention to the advertising than the storyline. These films were usually not just low-budget but almost no-budget, poorly shot, poorly acted, poorly written. But they had a visceral appeal — usually visceral in literal terms because what they lacked in refinement or insights about the human condition they made up in shock and outrageousness. Despite their undisguised origins as purely commercial — exploitation king Roger Corman is proudly the only producer in history who has made money on every single film — these movies have an unpretentious appeal and even a gritty sincerity that can hold up well against Hollywood confections, especially those that try to hide their resolute commercialism under a veil of pomposity.

Tarantino and Rodriguez have re-created an evening at a grindhouse or a drive-in, circa 1970. It’s a double feature complete with fake trailers (from up and coming directors Eli Roth of Hostel, Edgar Wright (Shawn of the Dead, and Rob Zombie House of 1000 Corpses) and a commercial for the restaurant next door (note that characters from the movie are drinking sodas with its logo), faux scratches on the film and “missing frames” and reels and perfect replica opening credits. Somehow, the stories retain their 70’s vibes, even though they include a few updates like text messaging and references to the war in Iraq.

The first movie is “Planet Terror,” a zombiefest directed by Rodriguez. A pole dancer named Cherry Darling (Rose McGowan of “Charmed”), her former boyfriend Wray (Freddie Rodriguez of Showtime’s “Six Feet Under”), a sheriff (Terminator’s Michael Biehn) and his barbecueing brother (Jeff Fahey), an adulterous doctor with three big needles of anesthetic, and her squabbling twin babysitters face off against some oozing flesh-eaters in a battle so completely over-the-top that it almost makes sense when the lovely leg that got chomped off is replaced by a machine gun as a prosthetic. Talk about your pistol-packin’ mama. And when the zombies come, it’s like the “Thriller” video, without the dancing — or the happy ending.

The second film, directed by Tarantino, is “Death Proof,” starring Kurt Russell as Stuntman Mike, a guy who drives a souped-up “death proof” stunt car and likes to use it as a weapon of mass destruction. Some of the pretty ladies he goes after include Sydney Poitier (daughter of the Oscar-winner), Tracie Toms and Rosario Dawson (both from Rent), and Mary Elizabeth Winstead (who appeared with Russell in the very different Sky High). This film has some characteristically choice Tarantino dialogue, cheerfully profane, hilariously frank, and divinely corkscrew, like a mash-up between Preston Sturges and Richard Pryor. The first half is mostly talk, talk that manages to mingle street insults, girly confidences, and Robert Frost, plus of course a lot of movie name checks. But when the don’t-take-rides-from-strangers action starts, it is stunning.

The break-out star here is real-life stuntwoman Zoe Bell (playing a stuntwoman named Zoe). She more than holds her own as an actress — while she is in the midst of one of the most astonishing stunts in movie history, the “captain’s mast” — with a devilish sizzle and fearless spirit that seem completely natural and utterly engaging.

Rodriguez and Tarantino also bring high spirits that give an organic brio to their mastery of story, tone, and visual story-telling. Their unabashed affection for the grindhouse genre keeps them from becoming arch, po-mo, or self-consciously ironic. This is a tribute, not a parody. At times, they seem to fetishize everything, even the literal film stock itself. There are loving close-ups of female curves, gleaming weapons, and gory wounds. There is sheer delight in the over-the-topiness: when someone says “no-brainer,” he means it literally. They have honored the sources that inspired and entertained them with a low-down, dirty, crazy, joyride that is packing heat, along with some nastily entertaining thrills.

Parents should know that this film includes just about everything that could be of concern in evaluating its appropriateness. It has non-stop intense, gross, graphic, grisly, and disgusting images of violence, including zombies chomping on bodies, attempted rape, torture, and every possible kind of homicidal butchery. Characters use very strong language, smoke, drink, and smoke marijuana. There is nudity, and there are sexual references and situations including a same-sex kiss and adultery. A strength of the movie is the portrayal of loyal friendships between diverse characters.

Audiences who see this movie should talk about how some of today’s most acclaimed directors were inspired by low-budget movies with no artistic aspirations.

Audiences who appreciate this movie will appreciate the other films by its directors, including Pulp Fiction and the Robert Rodriguez Mexico Trilogy, (El Mariachi, Desperado, and Once Upon A Time In Mexico). They may also enjoy some of the movies that inspired this one, including Dirty Mary Crazy Larry, Russ Meyer’s Faster Pussycat Kill!..kill!, Vanishing Point, and Gone in 60 Seconds (the original, of course). And they will enjoy the comic books that inspired some of these movies, like those collected in The EC Archives: Tales From The Crypt Volume 1.