Returning all too briefly from a long hiatus to remind us how provocative and powerful a science-fiction drama can be, Battlestar Galactica dives headfirst into the moral quicksand of war in an excellent movie-length special titled Razor.

The "razors" referred to here aren't ships or weapons but warriors stripped of fear and all ethical qualms. These "heroes" are asked to commit inhuman atrocities if necessary, in order to vanquish the apocalyptic threat posed by the robotic Cylon menace.

"This war is forcing us all to become razors. Because if we don't, we don't survive. And then we don't have the luxury of becoming simply human again," says the tough-as-tungsten Pegasus admiral Helena Cain (the formidable Michelle Forbes), whose ruthlessness is legendary to Galactica fans. On this unflinching series, women are often the sharpest, deadliest razors of all.

Humanity is among the first casualties in Razor, which unfolds as a flashback 10 months earlier aboard Pegasus, a battlestar separated from the colonial fleet in the immediate aftermath of the Cylon attack. Outnumbered, outgunned and betrayed from within by Cylons in human form, Cain and her crew make unforgivable choices in unforgiving circumstances.

The newest razor in Cain's arsenal is young but hardly naive protégée Kendra Shaw (impressive newcomer Stephanie Jacobsen), who survives Cain's reign to become an officer under Pegasus' present-day commander, Lee Adama (Jamie Bamber). Still haunted by her past, Shaw teams with Starbuck (Katee Sackhoff) on a dangerous mission that revives psychic scars.

Razor is as thrilling as it is sobering and disturbing, a potent combination that leaves us eagerly awaiting Galactica's fourth and regrettably final season next year.

Battlestar Galactica: Razor  airs Saturday, Nov. 24, at 9 pm/ET on the Sci Fi Channel.

Shrek the Halls

What a great idea for ABC to pair one of the most timeless holiday cartoons, How the Grinch Stole Christmas, with a kooky new keeper about another green-skinned grouch, this one bellowing, "No one here gives a hoot about Christmas!" Shrek the Halls takes the hit movie characters (and voices) and sets them loose on yuletide with a frenetic series of sight gags that embrace the grody and the sweetly goofy.  For Shrek, the ogre turned family man, company means misery, even at Christmas. Goaded by Donkey into decorating — a toilet-seat wreath hangs on the front door — Shrek reluctantly opens his home to a wacky menagerie, each with its  own star turn. (I howled when Puss in Boots halts his "Santa Claws" story after becoming mesmerized by the ball on his Santa hat.) As Shrek wishes "A smelly Christmas to all and to all a gross night," you may be appallingly charmed.

Shrek the Halls airs Wednesday, Nov. 28, at 8 pm/ET on ABC.