Generally, prequels don’t make for exciting stories because there’s not a lot of room for suspense. You know how things have to end in order for the original movie to take place. That’s one of the many reasons why people were so disappointed in the new “Star Wars” trilogy.

Patton Oswalt, one of this generation’s greatest comedians, has a classic bit about Lucas’ prequels in which he equates them to a big bag of rock salt and unmentionable parts of Jon Voight’s anatomy. You like ice cream and Angelina Jolie, right? Here’s where they started! The genius rant ends with him screaming in frustration, “I don’t care where the stuff I love comes from! I just love the stuff I love!”

As I watched the trailers for “X-Men: First Class” over the last few months, visions of rock salt kept running through my head. We already know that Professor X and Magneto used to be friends but now they’re on opposing sides of a war. We know that one wasn’t always in a wheelchair and the other one discovered his powers in a Nazi concentration camp. Do we really need to see the events leading up to that?

As it turns out, yes. We absolutely need to see them. Even though the film re-answers a lot of questions, it does so by telling a brand new story, full of compelling characters, interesting subtext, visually engaging action sequences and phenomenal performances. I thought “First Class” was going to be yet another superhero retread, but turns out it’s one of the best movies of the year so far.

Before Charles Xavier (James McAvoy) and Erik Lensherr (Michael Fassbender) became the leaders of two wildly different groups of mutants, they spent many years coming to terms with their abilities. For Charles, that meant using his telepathy (and vast fortune) to impress girls and attend distinguished universities. Trailing behind him like a lovesick puppy is his childhood friend Raven (Jennifer Lawrence), a blue-skinned beauty who has the power to mimic the appearance of others. Those who’ve seen the previous X-flicks know she eventually becomes Mystique.

Erik’s road to fully embracing his power of manipulating metal was a much darker one. His mother was murdered by a Nazi scientist (Kevin Bacon, gleefully chewing the scenery), and he has spent the years after World War II tracking down Nazis and returning the favor. (For the record, I would watch the heck out of a movie solely about Magneto traveling the globe to kill Nazis. Take note, Hollywood execs.)

Eventually Erik’s journey puts him directly in Charles’ path, as the two of them realize they’re looking for the same guy. The mother-murdering scientist now goes by the name Sebastian Shaw and he’s enacting a plan that will annihilate humans to elevate mutants to the top of the evolutionary food chain.

To stop Shaw, they recruit a number of younger mutants, some with recognizable names and abilities, along with a few new faces. Together, they must face down a truly evil villain and save the world in the process. There are also some fun surprises along the way.

What keeps “First Class” from being just another prequel/reboot is the obvious love that director Matthew Vaughn has for the material. The screenplay (which Vaughn co-wrote with Ashley Miller, Zack Stentz and Jane Goldman) does more than just connect the dots to other entries in the franchise; it tells a compelling and intricate story. Combine that with Vaughn’s flair for visuals (setting the flick during the 1960s was a brilliant move in respect to both historical references and costume design) and you’ve got the best “X-Men” film to date.

Another reason for the movie’s success is the inspired casting. McAvoy and Fassbender are phenomenal choices for Professor X and Magneto, particularly in how they infuse their performances with shades of Patrick Stewart and Ian McKellen (who played the roles in previous installments) while also creating their own versions of the characters.

Lawrence is the flick’s other standout. The Oscar nominee brings just the right amount of loyalty, cynicism and heartbreak to Raven so that you understand the reasons for the choices she makes in the future. I can’t wait to see her in next year’s adaptation of “The Hunger Games.”

My only gripe with the film is that there simply isn’t time (even at 132 minutes) to give equal attention to all the promising characters introduced throughout the story. That’s why I truly hope that “First Class” does well enough to warrant a sequel. I say pretend the other four movies don’t exist and start from scratch here. Seeing how Wolverine, Cyclops, Storm and others are introduced in this interpretation of the narrative would be a joy to watch.

“X-Men: First Class” is rated PG-13 for intense sequences of action and violence, some sexual content including brief partial nudity and language.