"Father Murphy," Michael Landon's new NBC series, sticks to the ribs like hot oatmeal. It doesn't stick to the brain, of course, but little television does. This new NBC series about life in a frontier town may prove as popular and durable as Landon's "Little House on the Prairie"; like that show, it's tolerably, disarmingly innocuous and provides a kind of positive family drama too rare on the air.

Landon wrote and directed the two-hour premiere -- at 8 tonight on Channel 4 -- which very advantageously transplants two actors who were regulars on "Little House": Merlin Olsen, the former L.A. Rams defensive linesman who plays the peaceable giant of the title, and Moses Gunn, who as Murphy's friend brings far more to the sidekick role than is in the script.

There's something bracingly unashamed about how elementary the concept is; in the premiere, Olsen not only shames a vile bully and rids a mining town of its vicious overlord, he also takes a hankerin' to the schoolmarm. Fortunately, the hankering is mutual. As the teacher, Katherine Cannon makes an agreeably spunky heroine, though she is saddled with the worst line of dialogue Landon wrote when she has to scold Olsen and Timothy Gibbs as young brat Will Adams, "A grown man talkin' just like a boy and a boy talkin' just like the grown man who's talkin' like a boy!" How's that again?

It is Olsen who makes the show work; he is a magnificently genial specimen, a strong and assertive father-figure type who is nonetheless the picture of calm and reason. Nothing about Olsen rings phony; he's one former athlete who can strut and fret before the camera without making a fool of himself. Whether bedding down one chilly night with naught but his faithful old dawg, or joining Gunn for a spin around the room at a woman-less frontier dance, Olsen retains a terrific and imposing dignity. When Cannon says to him, "You're quite a man, John Michael Murphy," it doesn't sound like hyperbole.

For young viewers, whose male role models on the air are usually either cartoonish superheroes or simpering sitcom dads, Olsen represents welcome and refreshing revisionism. Of course, faithful old dawgs help, too. When the time comes to rid the world of the villain -- a merciless businessman who has massacred settlers in order to steal their gold claims -- Landon is too reluctant to bring the pacifist to action against him. So he sort of drops a dog on him; the villain has pulled a gun on the hero and then, with a whump, the dog comes down like a discarded watermelon. The villain dies by his own bullet.

Later, it's our trusty canine pal who suggests to the hero a way that he can save the orphans of the massacred settlers from the hypocritical ninnies (a pair of dark churchfolk right out of Dickens) who want to haul them off to a cold institution. The hound gestures with his nose toward the robes of the priest slain in the attack and -- boinnnng -- Father Murphy is born. He will, according to NBC, occasionally don the priest's garb as a way of fending off the world's ills. At least it's for a good cause. So is "Father Murphy."

"Will you stay?" asks the schoolmarm. "Until they send a proper priest," says Murphy. "Could be a long time," says the schoolmarm. "That's fine, too," Murphy replies. "Fine" isn't the half of it.