It is absurdly difficult to make a good movie about sword-wielding medieval types who cast spells and wear tunics. It is even harder when one of your main characters is a magician who turns himself into a puppy. Nor do you do yourself any favors by giving the bad guys laser guns.

Do I speak of “Krull,” the addlepated fantasy-world cheesefest from 1983? I do indeed, my friends. “Krull” is a film that dares you not to laugh at it. Its plot reads like a oral report on “Lord of the Rings” given by a student who hasn’t read the book. At a time when films like “Conan the Barbarian” were bringing people into theaters, “Krull” was making them say, “You know what? Let’s stay home and take a nap instead.”

The people on the planet Krull — oh, did I not mention that this takes place on another planet? WELL, IT DOES — are minding their own business one day when, whoops, hordes of aliens arrive and start killing them all with their laser guns, which they have but the Krullers do not. It is still the Dark Ages on Krull, but it’s the Future on whatever planet the invaders came from. The Krullers refer to the invaders as Slayers, probably because of the heavy metal band they listen to, and two warring kingdoms on Krull join together to fight against their common enemy.

This is done by having the prince of one kingdom marry the princess of the other — which is what the young couple, who are in love, wanted to do in the first place, only they couldn’t because their kingdoms were at war. But no sooner have Prince Colwyn and Princess Lyssa said “I do” than the Slayers barge into the castle without so much as an RSVP and kill the whole wedding party. Colwyn survives, Lyssa is carried away as a hostage, and the guests are spared having to attend the reception.

Colwyn, a blond, grinning dope in tight pants, is patched up by an old man known as the Old One, who appears out of nowhere and was apparently hanging out in the mountains, safe from harm, until he sensed that a wimpy prince had been injured, and then he sprang into action. The Old One tells Colwyn that before they can venture to the Black Fortress, where Lyssa is being held, they must first retrieve the glaive, which for full effect should be pronounced in the voice of Prof. Frink on “The Simpsons.” (GLAAAAAIIIIVE!) In real life a glaive is a blade on the end of a pole, but in “Krull” it’s a starfish-shaped throwing disk. The Old One tells Corwyn that obtaining the glaive will be VERY DANGEROUS!, but then it turns out Corwyn only has to hike up a hill and pick it up out of some very shallow lava.

This is a running theme in “Krull.” We’re constantly told that there’s only ONE WAY! to do something, and that it’s VERY DANGEROUS!, and then when the characters fail to do it there’s suddenly ANOTHER WAY! that is also VERY DANGEROUS! And if that way fails, too, you can bet there will be YET ANOTHER WAY! to do the thing that there was originally only ONE WAY! to do. To use a screenwriting metaphor, this is like painting yourself into a corner and then avoiding stepping on the fresh paint by suddenly developing the ability to levitate.

Just as in Lord of the Rings, Colwyn and the Old One pick up some strays on their journey, and some of them seem kind of English. First is a magician named Ergo who comically attempts to turn people into animals but always winds up turning himself into animals instead. You can imagine how funny this is. In fact, you will have to imagine it, because the movie fails to make it funny at all. Ergo is the film’s “comic relief,” by which I mean if you are laughing he will help you stop.

Then there’s a band of men committing highway robbery — not like the guys who run the concessions stand at the ballpark, but actual highway robbers. For some reason, they decide to join Corwyn’s almost-certainly-deadly quest rather than simply robbing and killing him. This makes me wonder what kind of highwaymen they really are. Also, one of them is Liam Neeson, from back before he and Ralph Fiennes became the same person.

Our heroes cannot simply sneak up to the Black Fortress and rescue Lyssa, though, because the Black Fortress magically changes locations every morning, which makes things difficult when the Slayers are expecting a package. For security reasons, the Black Fortress does not post its itinerary on its website. But there is ONE WAY! to find out where it will be tomorrow: ask the old blind man who can foretell the future. The blind man, who lives in a cave with a little boy (don’t bother asking what that’s all about), has ONE WAY! of discerning the Black Fortress’ movements, and that is to peer into a magic emerald. But while he’s doing it, the Beast that controls the Slayers uses his own magic from afar to destroy the emerald. But wait! There is ANOTHER WAY! to find out where the Black Fortress is scheduled to appear tomorrow! If they go to the Emerald Temple, the Beast’s powers will be unable to stop them. Needless to say, the Emerald Temple is far away, there’s only ONE WAY! to get there, it’s VERY DANGEROUS!, etc.

So: more journeying. There’s a lot of journeying in this movie. If you enjoy watching people walk through forests, “Krull” may cause your head to explode with delight. The group finds a cyclops along the way who’s very polite and quiet. He says his race used to have the regular number of eyes (two), but then they were cursed to have one eye removed, and I guess the remaining eye sort of migrated to the middle of the forehead. (He’s not clear on that point.) Anyway, he’s helpful.

The group also encounters some quicksand. “The ground! It’s sinking!” declares one person, for the benefit of audiences members who have stopped looking at the screen and started playing with their iPhones. “It is the power of the Beast!” says another, but no — it’s only quicksand. That fellow is like the boy who cried Beast. But the Beast does use one of its powers, the power of shapeshifting, which is a power that the movie forgot to mention the Beast had until now, but oh yeah, the Beast can shapeshift, and it kills the old blind man and takes his place and infiltrates Corwyn’s posse. This plan is effective for approximately 3.4 seconds, and then the Beast is detected and the Slayer whose body it was using is killed.

With the old blind man gone, now there’s now way to find out where the Black Fortress will be tomorrow. Unless — no! It couldn’t be! Could it? I think — hang on — yes! It turns out there is ANOTHER WAY! As you probably expected, this other way involves the Old One climbing into a cave where the Widow of the Web lives with her giant spider. I mean, what else would it be? The Widow of the Web was the Old One’s girlfriend back in the day, and her name is Lyssa, just like the kidnapped princess. Evidently Lyssa was a very common name on Krull during this time. She gives the Old One a handful of sand, and somehow this is helpful.

Also: Ergo the incompetent magician turns himself into a puppy for a few hours to make the old blind man’s boy happy, because the boy had said he wished he had a puppy. He probably meant a puppy to play with and grow up with, not just borrow for the afternoon, but still. It was a nice gesture.

I guess I should also tell you what’s happening with Lyssa at the Black Fortress all this time. The Beast wants Lyssa to be his wife, though he is so far not pressing the issue too menacingly, which I respect in a demon. When Corwyn and the crew finally bust in to rescue her, she remembers that she can turn water into fire with her hands and shoot it at things, and that helps a little, though not as much as the handful of sand.

Against all odds, “Krull” crams itself with magic, fantasy, and heroic quests, yet still manages to be boring. This is an impressive feat in and of itself. You’d almost have to be doing it on purpose. I don’t know why you would do that, but I don’t know why Liam Neeson became Ralph Fiennes, either. There’s a lot I don’t know. And only ONE WAY! to find out!

(Note: The glaive that Corwyn retrieves does not play a significant role in any of Corwyn’s later accomplishments.)