After watching the first couple of minutes unfold in “A Knight’s Tale,” one quickly figures out that they’re going to have to get into a different frame of mind in order to enjoy the film. As soon as the opening medieval crowd chants Queen’s “We Will Rock You” with all the unity of a basketball audience, the realization comes about: This movie is not supposed to be taken seriously.

Taken at face value as some medieval fable about a peasant who rises to become the mightiest knight in the land, the movie surely falls flat. Anybody with a cursory knowledge of the Brothers Grimm can predict the direction of the plot. But taken as a comedy that has no pretenses to win an Oscar or alter the way one views medieval society, it is a good, entertaining – if a bit long – weekend afternoon popcorn movie. Still, the question must be asked: Why did an accomplished director like Brian Helgeland, who created the amazing and painstakingly historical “L.A. Confidential,” decide to make such a film?

Australian poster boy Heath Ledger plays William Thatcher, a peasant who enters a jousting tourney when the knight he serves suddenly dies. Winning the bout, he persuades two friends and a traveling Geoff Chaucer (Paul Bettany) to help him train so that he can win more tourneys and earn more gold pieces. Feigning a noble background in order to compete, the young William becomes increasingly successful as he meets the lovely, high maintenance woman of his dreams, Jocelyn (Shannyn Sossamon). She thinks he’s handsome and dashing and likes his cute, innocent peasant humility. He thinks she’s hot.

But as Helgeland paints the numbers of his script, he comes to the point where a villain needs to emerge. Enter the smug, aristocratic Count Adhemar (Rufus Sewell), a brilliant jouster who embodies all the hierarchical values William stands against. If you can’t guess the rest from here, I’m afraid you need to enroll in remedial English.

In a film that is basically a novelty, Helgeland recruited a lot of talented theatrical actors, and their performances are awfully good. Bettany’s Chaucer often steals the show with his charisma and comedic range, anchoring the film through its aimless points. Twenty-year-old newcomer Sossamon also delivers a convincing performance despite her character’s lack of dimension. Ledger is pretty decent throughout the film, although at times his earnestness borders on overwhelming.

But the question remains, why did Helgeland decide to include so many classic rock songs in the film? Its presence degrades an otherwise convincing period piece into a pulp fairy tale. There are enough serious performances in the film by talented actors to make the audience members want to invest themselves in its direction, but the presence of scenes where William trains to “Lowrider,” make the audience members sit back in their seats again as they realize they’re watching some escapist novelty.

The chief strengths of “A Knight’s Tale” lie in its exciting jousting scenes and period scenery. Helgeland’s tactful direction brings these scenes to life in a fashion that downplays the negative violence. Still, when one leaves the theater, the question arises: “Was I supposed to laugh at that or with that?”