Those wonderful folks at NBC who brought you "Misfits of Science" and "V" now bring you a new sci-fi adventure - Quantum Leap.

"Misfits" put the accent on fantastic science and "V" brought on the lizard-skinned aliens who gobbled live mice. Now, "Quantum Leap" turns to time travel - but backwards, not into the future.The show, which airs as a two-hour preview Sunday at 8 p.m. on Ch. 2, will assume its regular spot on the NBC lineup on Friday at 8 p.m., bumping "Miami Vice," which goes on hiatus.

Scott Bakula, who starred in "Eisenhower and Lutz" on CBS, plays Sam Beckett, a genius scientist whose has been bounced into the past in a premature time travel experiment.

For those who thought quantum was that Indian who taught the pilgrims how to grow corn (that was Squanto), the dictionary says a quantum leap is "any sudden and extensive change or advance, as in a program or policy."

In the preview adventure, Bennett's leap is backward from the near future to 1956.

He awakens in the body of an Air Force test pilot, one of the corps that is testing the X-2 rocket ship at supersonic speeds out of Edwards Air Force Base in the California desert.

His new body is lying next to a six-months pregnant woman he does not recognize. There's a little boy who calls him Daddy. The viewer sees him as he really is, but when he looks in the mirror, it reflects a stranger. He cannot remember who he is or how he got to where he is.

The real clincher comes when he learns he is expected to fly the X-2.

Along comes Dean Stockwell as Albert, an eccentric ex-astronaut from Beckett's time, who serves as a holographic observer, visible only to Beckett. He comes in mighty handy when it's time to ride the X-2.

It takes most of the show's two hours to get Beckett out of the test pilot's body, but instead of returning to his own time, Beckett finds himself advanced only 12 years and in the body of a Texas baseball player who's going to come to bat in the bottom of the ninth for the Waco Bombers.

Beckett, it turns out, is trapped in time, and the scientist best able to figure out how to get him unsnared is himself - only he literally can't even remember his own name.

In each incarnation, Beckett changes the past for the better.

This is strictly silliness, amusing but less than gripping, despite the considerable charm of Bakula and, particularly, Stockwell, who is a pleasure to watch.

"Quantum Leap" is not going to have you jumping out of your seat. But Brandon Tartikoff, the programming wonder at NBC, is entitled to a few toys and - judging by the fact that he called "Misfits of Science" one of his favorite programs - this may be one of them.

-THE CONVENTIONAL WISDOM holds that women will watch shows about sensitive people coping with life, while men would rather watch car chases, shootouts and mud-wrestling.

Men (Saturday at 9 p.m., Ch. 4) goes against that maxim by showing men who turn to each other for support as they struggle to cope with the changing definitions of what it means to be a man in America today.

This is an ensemble effort. Ted Wass stars as Steven, a surgeon, bachelor and womanizer. Saul Rubinek plays Paul, a newspaper columnist who is still in love with his ex-wife. Ving Rhames is Charlie, a lawyer and family man. Finally, Tom O'Brien plays Danny, a young, quick-tempered cop whose older brother, Thomas, gets killed in the opening episode.

The group includes an Irish-, Polish-, Jewish- and black-American, all high school buddies who retain their friendship, play poker and shoot hoops together.

The idea for the show is solid, but its execution in the opening episode is shaky - something that could improve after the audience gets used to everybody and can identify the boys without a roll call. Whether it will get that chance, opposite "Hunter" on NBC, remains to be seen. It can't do worse than the show it replaces, "Murphy's Law."