MCQUEEN : The Untold Story of a Bad Boy in Hollywood <i> by Penina Spiegel (Doubleday: $17.95; 367 pp., illustrated) </i> : My Husband, My Friend <i> by Neile McQueen Toffel (Atheneum: $17.95; 327 pp., illustrated) </i>

Something happened with Steve McQueen. We felt it before we read the rumors of severe illness and followed his grisly tabloid search for cure. There was the break in his work after “The Towering Inferno.” There was the end of one long marriage, and the evidently passionate but unsuitable union with Ali MacGraw. Something had happened, and it had to do with a once-assured star losing his way.

There are two books about him now, one, “My Husband, My Friend,” by his wife of 15 years, an abiding friend who never lost contact with McQueen and was probably so committed to him she had small chance of getting out of love while he was still alive.

The other--”McQueen: The Untold Story of a Bad Boy in Hollywood”--is by a professional writer who has worked hard to explore McQueen’s early years and to interview many of the actor’s cronies: She dedicates her book to her agent, to Steve and to those who loved the actor. But if you can work your way through Penina Spiegel’s breathless, punchy prose, I doubt if you’ll end up admiring McQueen.

Between them, the two books provide a lot of ugly detail. When you close them and look at the jacket pictures of McQueen, you begin to understand his suspicious, frightened and rather mean face. His is a story of deprivation, getting famous, megalomania, the alienation of old friends, drugs, promiscuity, violence to women and that boorishness which reckons it is so powerful it can do anything.

It’s the same story in both books--sad and spunky as told by Neile McQueen Toffel, unblinking and a little greedy in Penina Spiegel’s book. Any differences are those of points of view. The wife didn’t see the grim orgies with pickups that Spiegel recounts. But she guessed, and stuck it out. She had one brief fling of her own (very coyly described, so we have to guess the man), and Steve, the chronic womanizer, turned into a figure of wrath and rebuke. Still, Neile slept with him sometimes after the divorce. Maybe it was habit, his sexual appeal, knowing there was a kid in there terrified to come out from behind the bleak macho growl. Neile McQueen knew the journey he had made, and she had given up her own promising career for his.

Life taught McQueen to mistrust those close to him--the father who deserted; the mother who farmed him out. He was an unquestionably rough kid from a town in Missouri. He owed more to Boys’ Republic and the Marines than to family ties, though years later, he thought his exposure to asbestos on board ships had started his cancer. That could be, but who knows whether cancer doesn’t also have to do with the bitterness that always sees how it has been wronged. McQueen was hard, but he had all the injured ego it takes to make a tough man want to be an actor.

Neither of these books considers the paradox, but there is a conflict of logic in his desire to be thought tough and his wish to enjoy the pampered, artificial existence of a movie star. You have to wonder how much McQueen hated his world and himself because he hadn’t been allowed to do that fence-vaulting motor-bike stunt in “The Great Escape.” It was essential to his reputation, but it hadn’t been him. As if to make up for it, he insisted on “Le Mans” being so “real” it had no story. That disaster lost him John Sturges (who directed McQueen in “The Magnificent Seven” and “The Great Escape”) and his wife. It was the start of the break.

For a year or so, he was a better actor. There is a depth, irony and pained mythic nobility in “Junior Bonner” and “The Getaway”--but they are both Sam Peckinpah, too.

If you wanted to put your finger on when “it” happened, maybe it was the day on “The Getaway” (vividly described by Spiegel) in which Steve had to hit MacGraw several times for the film, and got so charged by the scene he followed her to her home in the evening and made love to her on the floor. If anyone ever tries a McQueen biopic, there is the magical scene in which life works like a movie.

The second marriage reads as black comedy for the observers, and sheer hell for the leads. It may have made McQueen feel the Fates were against him. The free-spirit image masked a conservative who could not get over his guilt at leaving a long-suffering wife and two children. He turned fat and shaggy; he lost his drive and his confidence.

Then comes the most extraordinary thing in his life. Out of some weird mixture of vanity, caprice and indifference, he said he would star in Ibsen’s “An Enemy of the People.” Had he read the play? Was it all to spite the ill-fated First Artists? Did he sniff glory? Or was it just that title that moved him?

Neile couldn’t recognize him when she saw the rough cut. “Forget it, kid!” she told him. “It’ll never sell.” It didn’t, and there was not much except pain and misery ahead.

So now we have public enemies-saviors like Rambo, camp with body oil and narcissism. Whereas, I can’t recall one moment in a McQueen film when he is dishonest. He wasn’t always good or eloquent, but when he was cast well, and if he could strip his lines down to a few words, once the camera got in to that unyielding, weary face you know you were watching one of the unerringly honest screen actors. And when you look at the teen pictures now, Steve McQueen seems like the last star of the 1940s, so tough he was ready to break.