WEEKEND TV : 2 NETWORK DRAMAS: NICE TRY, BUT . . .

When it comes to exposition and explanation, network dramas are usually excessive; less would definitely be more. But not always. A CBS movie and an NBC family special airing tonight go too far in trying to let viewers fill in some of the information about their characters.

Restraint is the guiding force in “The Room Upstairs,� CBS’ “Hallmark Hall of Fame� presentation that airs from 9 to 11 tonight on Channels 2 and 8. Adapted from a novel by Norma Levinson, it tries hard to go against the TV grain by being small and gentle--the story of a woman opening herself up to other people.

It tries so hard it hurts.

The problem is that in their quest to make the central character of Leah Lazenby enigmatic and introverted, writer Steve Lawson, director Stuart Margolin and star Stockard Channing have also made her contradictory and not particularly interesting.

Leah is portrayed paradoxically as gifted in working with retarded, psychopathic and abused children, yet unable or unwilling to connect with adults, having what she describes as a “basic indifference� to them. More puzzling, this loner has chosen to share her childhood home with boarders.

We see her at work with boss Linda Hunt and in her three-story Boston home with her tenants--who include a single, sensitive, altruistic musician played by Sam Waterston--but we never get much sense of why Leah is the way she is, nor of what’s at risk in making herself more vulnerable. “Even as a kid you were quirky,� her brother remarks.

Played at a rhythmless pace with a supporting cast of one-dimensional characters, Leah’s subtle evolution of personality simply doesn’t carry any emotional weight. This is a “Room� without furniture.

On the other hand, NBC’s “The Storyteller� has nearly everything going for it: intriguing characters, snappy special effects, fanciful makeup and costumes and a fresh, imaginative production style.

All that’s missing is a cohesive story.

Produced in London with Jim Henson as executive producer, “The Storyteller� (8:30 tonight on Channels 4, 36 and 39) is a pilot for a possible series that would dramatize old but not necessarily well-known European folk tales. It features John Hurt as the engaging storyteller, aided by a talking dog, and was directed by music-video veteran Steve Barron.

The concept and execution are first-rate, but the story, “Hans My Hedgehog,� is not. It tells of the troubled life of a child born half-boy, half-hedgehog. The promising premise delivers some good moments but they come in fits and don’t build on one another toward a big conclusion.

In that sense, Anthony Minghella’s script is an honest reflection of the story’s roots in oral narrative, but in the visual, more literal medium of television, a stronger dramatic line is needed.