Good news for science-fiction fans this weekend: the debut of a new series on USA Sunday, and the beginning of a new season of "Stargate: SG-1" tonight on Sci-Fi channel.

"The 4400" launches at 9 p.m. Sunday. It’s the story of people who have gone missing without a trace from the end of World War II through the present day who suddenly walk out of a ball of light that lands on Earth one day.

Michael Moriarty, Billy Campbell and Peter Coyote are the most recognizable faces in the series. However, the program focuses on a young, "X-Files"-like couple assigned to find out what happened to these people and just exactly what the truth is out there.

The saga begins in 1946 with an 8-year-old girl from Crescent City, Calif., who vanishes in a funnel of brilliant light from the skies. In rapid succession we watch as one person after another disappears the same way over the decades.

When they suddenly reappear on Earth from a comet-like spaceship, they are all the same age they were the day they disappeared, even though time has marched on in the lives of the people they knew. All of them are frustrated, except for the little girl, who seems serenely accepting of her fate even though her parents are dead and buried.

One of the missing isn’t taking any of this lying down, though. When he confronts people from his past, he inadvertently finds he has the power to shake things up.

Others have been imbued with supernatural abilities too.

"The 4400" comes from the people who produced "The Twilight Zone," "The Outer Limits" and "Star Trek" series but doesn’t seem as original, intellectually challenging or scary as any of those. Maybe it will get better.

Stargate opening

The debut features a surprise change in command as well as a space trip to thwart an alien enemy. "Stargate SG-1," the TV series, has never been as intriguing as the 1994 movie starring Kurt Russell and James Spader. But like all sci-fi sagas, it has developed a loyal core of followers who will be happy to see it back in their TV orbits.

Would-be Marthas

The television networks are in danger of reality overload with new reality shows arriving almost nightly. The latest one is "The Search for America’s Next Domestic Diva" at 9 Sunday night on ABC.

At least viewers won’t be teased along for weeks, because the winner is named at the end of the show. The program is an obvious play on the suspension of the "Martha Stewart Living" series as Stewart faces sentencing for her federal stock fraud conviction later this month. One of tonight’s six contestants even makes a reference to replacing her.

The half-dozen men and women selected to compete for the title won’t get a million dollars but will have a shot at making a TV pilot for a series like Stewart’s.

The contest borrows from many of the other reality shows with playoff games. A panel of three judges knocks contestants out of the running along the way, but none is as vicious as Simon Cowell. The winner comes as a surprise and a choice that Stewart loyalists might find hard to accept as a substitute.

Unless you’re hooked on this kind of thing, it’s all sort of stupid.

Also this weekend

# The swimming finals for the U.S. Olympic team are on tape at 8 tonight as NBC revs up the promotion machine for the summer games next month. The track and field tryouts are tomorrow night at 8.

# Three very different spy series from the 1960s reappear tonight when "The Saint" starring Roger Moore arrives at 8 on BBC America (Insight 104), followed by "The Avengers" starring Diana Rigg and Patrick Macnee at 9. "The Prisoner," with Patrick McGoohan, is at 10.

# The timid detective goes out on a date on "Monk" at 10 tonight on USA.

# "Missing" has its season premiere at 10 tomorrow night on Lifetime.

# ABC looks at TV bloopers over the past 50 years at 10 tomorrow night.

# John Kerry and John Edwards are interviewed together on "60 Minutes" at 7 p.m. Sunday on CBS.

# John Travolta is "Inside the Actors Studio" at 7 Sunday night on Bravo.

# "Trading Spaces," at 8 Sunday on TLC, lets viewers see how the show’s designers decorate their own digs.

# Wes Studi stars in "Thief of Time," a new "Mystery" offering, Sunday at 9 p.m. on KET2.

# Joely Fisher is back for another season as a private eye raising her sister’s kids on "Wild Card" at 10 p.m. Sunday on Lifetime.

# Gay marriage comes up in the next-to-last episode of "Queer as Folk" Sunday at 10 p.m. on Showtime.