As each new comic book adaptation hits the screen, I must reiterate regretfully that I have never been nuts about comic books. Thus, I can’t gauge these films based on their faithfulness to the source material. When it comes to “X-Men”, I am far from uninformed (I watched the Saturday morning animated series and wore out my thumbs on the video games), but issues of “The Uncanny X-Men” were never stacked by my bedside. The original film, released in July of 2000, was a slick and professional product, artfully translated to screen by Singer (“The Usual Suspects”), that depicted a society where “mutants” (or beings with genetic abnormalities that, in some cases, give them special powers) exist among us. Both “X-Men” films understand the appeal of their superheroes, as they use their unique abilities to fight for good. “X2” features a league of these superheroes fighting for the ultimate good: rising against oppression and struggling for equality as a minority regarded with great fear. Taken as a moral fable applicable to areas of our own society, “X2” provides generous food for thought; as entertainment, it’s loads of fun, with strikingly realized (and very much three-dimensional) characters enriching some rather ingenious effects sequences. Just when you think you have seen the coolest thing in the movie, something even cooler reveals itself.

Professor Charles Xavier’s (Patrick Stewart) School for Gifted Youth is in jeopardy. After an assassination attempt on the President of the United States by teleporting blue mutant Nightcrawler (newcomer Alan Cumming), a special operation led by General William Stryker (Brian Cox) is authorized to infiltrate the school - in reality, a refuge where mutants can come to explore and understand their powers - and capture all those within. To prevent an impending war, the X-Men spring into action: taloned beast Wolverine (Hugh Jackman), telepath Jean Grey (Famke Janssen), weather-controlling Storm (Halle Berry), optical blast-firing Cyclops (James Marsden) and Rogue (Anna Paquin), who can drain someone’s life-force with a simple touch. Meanwhile, Ian McKellen returns as the metal-manipulating supervillain Magneto and has what is possibly the standout scene in the movie, when he makes a cunning and resourceful escape from his plastic prison.

Many cast members have made welcome advancements with their characters since “X-Men”. Berry seems infinitely more comfortable as Storm, while Janssen is more centered in the complicated skin of Jean Grey. Elsewhere, the amazing Brian Cox (“Adaptation”, “The Ring”) makes a formidable villain that you will love to hate, as a military scientist bent on the annihilation of all mutants. Cumming is wonderful as Nightcrawler, instilling the character with a fragile sense of innocence, with an opening White House invasion scene that is a total doozy. New, younger mutants are given beefier roles than expected - like Iceman (Shawn Ashmore), who has a great method of chilling soft drinks, and Pryo (Aaron Stanford), who can turn fire into a projectile weapon - and both are outstanding additions. Rebecca Romijn-Stamos once again makes an impression as sultry shape-shifter Mystique, while Yuriko (Kelly Hu), Stryker’s chief henchwoman, has a certain ability that makes her the perfect foil for Wolverine in an incredible and aggressive mano-a-mano brawl during the film’s climax, set at a military base inside a giant dam.

But wait, there are even more mutants to identity. Some brief cameos include Jubilee, Kitty Pryde, and (best of all) Colossus. Had I been a more avid fan of the X-Men universe since childhood, I have little doubt I would have been wetting my pants during his kick-ass appearance. But the standout remains Hugh Jackman as tortured amnesiac Wolverine, who unleashes his berserker rage in spectacular fashion, but also represents the heart of “X2” - a vulnerable hero struggling to find himself in a harsh and hateful world.

Singer and co-writers Michael Dougherty and Daniel P. Harris do a generally commendable job with juggling the landslide of characters, and the most interesting and compelling heroes are handily positioned in major roles. “X2” gets a little long in the tooth during its last leg, crippling the pace and halting some of the momentum. But this and other minor drawbacks will do little to prevent the film from emerging as one of the finest the summer season will have to offer. Thoughtful, intelligent, assured and exciting, “X2” is a rare sequel that trumps its predecessor, and an evolutionary leap forward for comic book movies.