If every summer blockbuster or comic-book movie were as unexpectedly entertaining as Marvel’s “Guardians of the Galaxy”, I’d greet the upcoming summer flicks with a lot more enthusiasm…but there aren’t many writer-directors as witty as James Gunn. Indeed, it’s the writing that sets his film apart from the crowd, in harmony with perfect casting, first-rate visual effects, and other key ingredients. Like so many other Marvel films, “Guardians” assumes that you’ve already read the books and memorized the characters and their stories. It isn’t easy to follow all the exposition if you’re not familiar with the characters, but before long if becomes clear who’s worth cheering for. The story, which Gunn conceived with Nicole Perlman, establishes territorial tension among 5 unusual characters, presents them with a way to work out their problems, and unites them against a common enemy. The group of “misfits” includes a hilarious raccoon with a badass attitude (voiced by Bradley Cooper), an anthropomorphic tree named Groot (voiced by Vin Diesel), a feisty and dangerous woman (Zoë Saldana), a hulk-like figure seeking revenge (WWE star Dave Bautista), and a smartass orphan from earth played by Chris Pratt. As for the performances, there’s no weak link here as everyone gets the chance to shine. Best of all, the movie has a great villain; Lee Pace sinks his teeth into the evil Ronan. He’s sly, dangerous and cruel. It’s a delicious performance. Finally, Gunn has injected a welcome dose of humor to his screenplay. With a sure-footed sense of pacing, he has punctuated his screenplay with wonderfully funny dialogue. It’s the second superhero movie (after “The Avengers”) I can think of that has made me laugh out loud, repeatedly.

We can only invest in a superhero movie if we root for the characters and believe that something is at stake. Gunn gives us all of that and more, in a film that clocks in at two hours but never seems long. “Guardians of the Galaxy” is definitely the surprise hit of the summer.

Rating: 3/4