by JULIET WATERS

It's easy to see why Jonathan Lethem's The Fortress of Solitude has become this year's big book. It has the whimsy of last year's big book, Middlesex, the scope of the previous year's big book, The Corrections, and the hipness of the big book before that, A Heartbreaking Work of Staggering Genius. If this wasn't enough, the novel's protagonist grows up to be a critic, which has an obvious appeal to reviewers. Fortress is the messiest and the most flawed of all these books. Still, it's the one readers will probably love the most and longest, even while they're arguing over what's wrong with it.

Dylan Ebdus's credentials as a rock critic are impeccable. One of a handful of white kids to grow up in his Brooklyn neighbourhood in the late '60s and '70s, his insanely negligent bohemian mother boasts to a friend that he's one of the only three white kids in his public school - not his class, his school. A sensitive, imaginative introvert, Dylan is doomed to daily physical and psychological brutality. "Play That Funky Music White Boy" becomes the menacing pop soundtrack of his young life.

When he befriends Mingus Rude, the son of a major soul singer, he gets the occasional respite from his suicide mission of integrating in a hopeless public school system. Their impossible friendship is the core of this book. As underground graffiti artists, their creative partnership becomes something more when Dylan is given a ring by Aeroman, a dying, black, alcoholic superhero - a ring that gives the wearer the power of flight.

This is where things start to get problematic and where readers will start to divide. Until this point, Fortress of Solitude has been proceeding with all the gravitas expected from what starts as a social history of late-20th-century Brooklyn. It's hard to tell whether "Underberg," the title of the first part this novel is meant as a tribute or a gentle parody of Don Delillo's Underworld, another big book of recent years. The overwritten socio-poetic tone of this section hints that Lethem might have been reading a lot of Delillo to get himself through these difficult chapters. Drawn from Lethem's own childhood, this part contains the most interesting and powerful material, but the tone has a distancing effect.

Later in the novel, Dylan's girlfriend will point to his massive CD collection and accuse him of creating a Wall of Moods to mask his own depression. One could throw the same accusation at Lethem. Though much of the writing in this first part is exceptional, sometimes it works as a wall of words numbing his own memories of what must have been an oppressive childhood.

The ring and the silliness it introduces has a liberating effect. It seems to free Lethem from the responsibility he's taken on. At the same time he's shirking nothing, since the ring highlights the absurdity of reparative adolescent superhero fantasies. All the superpowers in the world can do nothing to stop the worst source of crime: public indifference, the most impenetrable fortress of all.

By the time this plot device is introduced, however, the most interesting story, Dylan's childhood, is over. Fortunately, Dylan's father keeps the novel grounded. Abraham Ebdus's struggle to stay true to his own artistic vision, while paying the mortgage designing covers for science-fiction books, gives the book a back bone that keeps it steady during some dangerously shallow waters. Dave Eggers is right when he wrote that there are few things more unbearable than fiction about people in their 20s. Wisely, Lethem keeps the section about Dylan's college years short and sweet. Dylan's years as a rock critic and his return to Brooklyn may leave some readers unsatisfied as well.

For all its flaws, however, this is more than a big book. It's an important book that dares to take on the most difficult issues of our era, a task beyond the powers of the strongest superhero, let alone a mere writer.

The Fortress of Solitude by Jonathan Lethem,
Doubleday, hc, 511pp, $37.95