Television critic Mike Hughes offers these recommendations for weekend viewing:

FRIDAY MUST SEES: 'BATTLESTAR GALACTICA,' 'FRIDAY NIGHT LIGHTS'

"Battlestar Galactica" finale, 6 p.m., Sci Fi Channel (repeats at 8:11 p.m.).

One of the great TV series wraps up tonight, with a showdown that involved the future of humankind. Science-fiction likes big themes.

The one chance left, it seems, is to invade a Cylon stronghold and retrieve the kidnapped girl who is half-human, half-Cylon. She may hold the ultimate answer, including the route to Earth. This is a daring mission, done by an all-volunteer force.

That might become just a big-hardware shoot-em-up, but we have faith. So far, "Galactica" has invested everything it does with rich intelligence.

"Friday Night Lights," 8 p.m., NBC.

Parents and teens have lots of troubles tonight.

In Coach Taylor's family, an accidental discovery leaves Julie in trouble. There's an angry silence, then an extraordinarily good scene with her mom.

In the Garrity family, it's the dad (Buddy) who misbehaves -- often and extremely. His daughter Lyla has had enough.

All of that is mixed in with the football play-offs, a turning point for Landry and even the possibility of romance for the freshman quarterback. It's another excellent episode.

SATURDAY'S MUST SEE: 'CASTLE' (AND BASKETBALL)

"Castle," 9:02 p.m., ABC.

This is a chance to catch the rerun of the second "Castle" episode, which built on the potential of the first one.

In the opener, we saw the dueling relationship between Richard Castle (Nathan Fillion), a witty crime novelist, and Kate Beckett (Stana Katic), the intense police detective he's shadowing.

In this second hour, things are spread around. Beckett gets some of the clever lines; so do her colleagues.

More importantly, we -- and Castle -- begin to see her as a smart and caring cop. This story, about the death of a nanny, keeps taking new twists, allowing everyone to be right and wrong. With new episodes at 9 p.m. Mondays, "Castle" is one to keep an eye on.

Basketball, all day, CBS and ESPN2.

The second round of the men's NCAA tournament begins today on CBS, with doubleheaders at 7 a.m. and 2 p.m.. By Sunday, the tourney will have its sweet 16.

Meanwhile, the women's tournament starts on ESPN2. It has doubleheaders at 6 a.m. and 2 p.m.

SUNDAY'S MUST SEES: 'DESPERATE HOUSEWIVES,' 'KINGS'

"Desperate Housewives," 8 p.m. Sunday, ABC.

In a season focusing on smaller stories, this show returns tonight to big, life-and-death stuff.

Dave has been driven by revenge for a car crash that killed his wife and daughter. He changed his name, married Edie, moved into Wisteria Lane and befriended Mike -- who apparently was the other driver in the crash.

Now Dave has schemed to take Mike and Katherine on a camping trip. Someone will be killed, ABC implies.

Meanwhile, Edie gets closer to the truth. Also, Lynette has trouble at work and Bree, startled by her husband's kleptomania, considers selling her business to save her marriage

"Kings," 7 p.m., NBC.

Last week's terrific opener had opposites collide. David Shepherd is a quiet, country guy who accidentally became a war hero. King Silas is eloquent and bombastic, with grand visions for himself and his country.

David forced a cease-fire, enraging the king's brother-in-law -- a military mogul who promptly drained the country's treasury. Tonight, amid peace talks, the schemes continue.

All of this is loosely based on the biblical story of David, but it works as grand palace intrigue for any era. It's an epic story, filled with human touches and compelling work by Ian McShane as Silas.