In medieval times, the search for the mythic "Secret of Secrets", the key to gold and eternal life, is continued by alchemist and magician Boecius (Klaus Kinski), who is part of the Count's inner circle of advisors. But today he happens upon a breakthrough which causes the sky to light up thanks to his spell casting, the only trrouble being that the locals around the castle think that the light was a dragon and threaten to revolt should nobody go and try to vanquish it. The Count's bravest knight, Klever (Harvey Keitel), is despatched to see about this, but they would be better off keeping an eye on the Princess Alba (Maria Lamor)...
One of the joys of watching obscure films is that every so often you'll see a familiar actor or actress in an unlikely role, and with Star Knight, no, it's Klaus Kinski you're surprised to see (he made over one hundred films before his untimely death at least), it's Mr Keitel. Now, I don't know his motives for appearing in this Spanish production, but he did his own dubbing and possibly thought it sounded like a bit of fun, a change from his usual tough guys. However, when you think "light comedy" his is not really the name which springs to mind.
Nevertheless, it's the comedy Keitel takes care of here as the vain Klever (an ironic appellation, one presumes), who thankfully is not a cowardly character but rather a brave to the point of foolhardiness one. Yet while this looks like someone has enjoyed one too many viewings of Excalibur, it's actually a science fiction romance set centuries ago because early on the Princess ventures forth into the countryside, stops at a lake, whips off all of her clothes and goes for a swim. Out in the water, there are suddenly bubbles breaking on the surface, not because of the Princess's hearty breakfast but because something lurks beneath and it's just grabbed her.
The Princess's maidservant rushes back to the castle with the bad news and that night Klever and his motley crew go to the lake to kill the dragon. Except it isn't a dragon, it's a spaceship and it rises out of the depths to fly off into the distance, something it does just about every time a character gets close to it. Fernando Rey (another star!) is in cahoots with Klever as Fray Lupo, the closest thing the film has to a villain, a priest who is forever trying to wangle more money out of the townsfolk and capitalises on their superstition to get his own way. These two will receive their comeuppance by the effects-filled finale.
As Fray Lupo claims the Princess will never return, he has to change his tune when she walks through the castle door, dazed but intact. It seems that she has fallen in love with the Star Knight of the title, the pilot of the spaceship played by singing sensation Miguel Bosé, a chap encased in a suit and helmet whose speech sounds like he's if running a wet finger around the rim of a wine glass. Naturally, Klever wanted the Princess's hand in marriage and sees the alien as a rival, so a jousting match ensues with surprising results. In amongst this, Kinski casts spells and gets his hands on an enchanted globe, then offers advice to the lovers in uncharacteristically avuncular guise. Star Knight makes more sense the longer it goes on, but even then it's a bit of a muddle; still, it's oddly endearing in its innocent way and the novelty of seeing a heavyweight like Keitel in something like this cannot be underestimated. Music by José Nieto.