There are no happy hookers on television, because it cannot be suggested that a life of play-for-pay leads to anything but misery. In "Sessions," the NBC movie at 9 tonight on Channel 4, Veronica Hamel plays about the unhappiest hooker ever, even if she is so successful she lives on Sutton Place and doles out $100 bills at Bergdorf-Goodman. Still, she's in a trance of angst from first frame to last.

It is a chillingly controlled and consistent performance, cunningly sensuous at times, but the film, written by Barbara Turner and directed by Richard Pearce to look as icy and austere as "Interiors," fails a basic requirement of dramaturgy; the protagonist doesn't really evolve or change to an appreciable degree over the course of her story.

She does go somewhere--literally, if not spiritually. The end of the film has her packing her two cute but unexplained children into the Jaguar she earned horizontally and leaving New York for Los Angeles, surely the ideal place to shake off the sleazies. This isn't enough of an oomph for having endured two hours of ache-ache-ache and whither-whither-whither.

The title stands both for the prostitute's sessions with men and her sessions with a woman psychiatrist. In the shrink's office, the woman known as "Randy" to her clientele and "Leigh Churchill" to family and friends makes such dour observations as:

"I'm not sure exactly what I need to know; I just need to know it."

"I've got so much rage inside of me, it's tangible. I can touch it."

"I have sex with men I wouldn't speak to on the street."

And this feminist manifesto: "After you take away all the garbage, there's nothing men want from women but sex or to perpetuate themselves through child bearing. If they could do that alone, they'd probably prefer it. What's left is child-rearing and maid service."

A loyal male friend, Josh, tells her, "You really are one callous bitch" upon being thrown out of her life for a while, but the script, and Hamel's attentiveness to detail, show us, gradually, the fear and insecurity beneath. It just seems like an awfully pat case study of a man-hater whose attitudes were shaped by a cold and distant father.

Some of the sessions with Randy's customers are painfully trenchant, however. In post-coital conversation, she will obligingly tell a man, "You're great, you're the best, you're the very best" or "You're really something, you're really terrific," and fool that he is, he'll believe her, or appear to. A voice on the phone tells her that her next client enjoys "straightforward spanking," and from that we cut to a scene of the man sobbing, on his knees, and listening to her consolation: "Mommy loves you, you're a good boy."

There is a lot of bitter and appalling truth in "Sessions," even if the total film seems hesitant and unresolved.

Among the supporting players, Jeffrey DeMunn paints patient Walter, a boyfriend who doesn't know his lover is a pro, a distinctive shade of gray, and Jill Eikenberry, as one of Leigh's friends, seems more accomplished, and more attractive, than ever (she's like a bouquet of flowers), but the script misplaces her in the second hour. Ann Lange is touching as a fellow hooker who is beaten not by a client but by a blue-collar boyfriend.

"Sessions" has little to offer but the ancient news that the world is a cruel place, but at times it makes this grim observation with unusual and depressing effectiveness. Hamel can join Elizabeth Taylor ("Butterfield 8") and Jane Fonda ("Klute") in the screen hookers' hall of, for lack of a better word, fame. Note: CBS refused to screen in advance tonight's premieres of "AfterMASH" and "Emerald Point, N.A.S."