X-Men didn't become a cultural phenomenon by accident. The series about a team of superheroic mutants, protecting a public that hates and fears them, rose from obscurity to become America's bestselling comic book around 25 years ago, thanks to the work of writer Chris Claremont and artists John Byrne and Terry Austin. It has mostly stayed at the top since then. X-Men: Days of Future Past (Marvel; paperback, $15.99) reprints the half-dozen issues from 1980 that ended Claremont and Byrne's collaboration, although both of their subsequent careers have pretty much coasted on their X-Men rep.

In particular, the two-part "Days of Future Past" story set the agenda for the next quarter-century's worth of X-Men adventures. (Both X-Men movies allude to it.) It's a sort of "La Jetee"-via-"Terminator 2" contraption, in which the team's new inductee, 13-year-old Kitty Pryde, has her mind psychically swapped with her future self by the X-Men of 2013, who are being exterminated by giant anti-mutant robots and desperately trying to change history to avert a nuclear catastrophe.

The secret of the Claremont/Byrne X-Men was that it combined full-throttle adventure stories with wrist-to-forehead soap opera. ("What do you say, what do you do, when the woman you love becomes . . . supremely powerful?" the tortured Cyclops muses in the opening recap of the series's first 15 years. "What do you do when she . . . dies?") Byrne draws with a graceful, blobby fluidity -- a more human variation on Jack Kirby's dynamic exaggerations -- and makes the stories seem more more consistent than they actually are. Claremont's writing is legendarily susceptible to parody -- when you see thought balloons so heavy with gobs of exposition and angst that they almost take over a panel, or when a character replies to "I love you" with "And I, you," you know you're in the Claremont Zone. But he also wrote outlandishly exciting action sequences in those days, and his melodrama is powered by one hell of a metaphor. His mutants are stand-ins for the despised Other (racial, sexual, whatever), whose existence poses a threat to the social order, and who is driven by the contempt of the public into underground subcultures with their own codes of ethics -- benevolent or destructive. What socially awkward young comic book reader couldn't relate?

-- Douglas Wolk