Movie critics are born and not made, at least if the professional development of TIME'S Jay Cocks is at all representative. "Even before I could read," he says, "I looked at the movie ads in the papers rather than the comics." Naturally, as a kid Cocks lived on a steady and omnivorous diet of films, but stopped short of skipping school to sit goggle-eyed before the big screen. "My parents were both educators, so hooky was out of the question." At Kenyon College in 1966, Cocks organized the campus' first film festival, then joined TIME in 1967.

He now sees about eight movies a week—"mostly through my own choice"—including oldies shown on TV and others occasionally on his home 16-mm. system. When reviewing a new film of unusual interest, Cocks might sit through it five times (though not necessarily consecutively) before rendering judgment.

Cocks first spotted this week's cover subject as "a really aces actor" in the early 1960s, when Jack Nicholson was gracing drive-in screens in horror movies. In writing the story, Cocks drew on correspondents' files and the research aid of Pat Gordon, taking time out for a few quick antiaircraft battles at his favorite pinball parlor. The writing done, he turned his manuscript over to Senior Editor Martha Duffy, who asked Cocks to wait while she gave his piece a once-over reading. "I'm going to the movies," he announced. "You're what?" said Duffy. "To the movies," repeated Cocks, already out of the office door. "I've gotta relax, you know."

Los Angeles Correspondent Leo Janos handled the bulk of the reporting, conducting eight hours of interviews with Nicholson at the actor's Los Angeles home. Before their first session Janos asked Nicholson for "a list of people in your life who may not be obvious to me—leave out close friends, former wife and girl friends."

The gregarious Nicholson reeled off more than 40 names. A few days later Janos was at Nicholson's house when "the phones—three separate lines—began ringing off the actor's wall." "My friends are reporting in from all over the place that they're being interviewed," Nicholson said, adding with some hyperbole: "It's like undergoing an FBI full-field check for a top-secret job. TIME marches on."