WHEN Aaron Sorkin's West Wing follow-up, Studio 60 On The Sunset Strip, was cancelled midway through its first season, many commentators said the reason was obvious. The West Wing was about people who run the world; Studio 60 is about people who make TV shows and movies - and the only people interested in that are other people making TV shows and movies.

Huh? Telling stories about life backstage at various dream factories didn't stop Singin' In The Rain or Sunset Boulevard becoming two of the most beloved movies of all time, or prevent The Larry Sanders Show from being one of the 10 greatest television series. Meanwhile, last time I looked, magazines devoted to the lives of the stars still seemed to be selling.

In any case, if no-one is interested in life on the other side of the screen, someone forgot to tell the people who keep making programmes about it. HBO's young-actors-at-large series Entourage (ITV2, Thursday) is rolling along to award-winning effect. Closer to home, Jennifer Saunders has unveiled her talkshow satire, The Life And Times Of Vivienne Vyle (BBC Two, Thursday), and Ricky Gervais's Extras Christmas Specials are in the can. Meanwhile, a glitzy new double dose of behind-the-scenes has arrived with Five's latest US imports, Californication and 30 Rock (Thursdays, Five).

The two are markedly different. Californication will get the most headlines - mainly because it features the most oral sex, including, in the opening scene, a nun on her knees in church. It's a dream sequence and an indication of how the programme will go. Californication sets the bar low for itself: the people who will be offended by depictions of fellating nuns will be offended; the people who think depictions of fellating nuns are dangerous, clever and radical will think it's those things. The rest of us will just continue missing The Sopranos.

The series follows the exploits of Hank Moody (David Duchovny), a New York writer who moved to Los Angeles when his angsty novel God Hates Us All was adapted for a movie. Of course, the studio philistines didn't get it, turning it into a rom-com called Crazy Little Thing Called Love, and Hank has sunk into a funk of writer's block, sulking around LA hating everyone in it.

Why doesn't he just go home? Because, his ex-partner, Karen (Natascha McElhone) and their 13-year-old daughter, Becca (Madeleine Martin; imagine Jeanette Krankie playing Emily Strange) are in LA, too, living with Karen's new fiancé and, despite his misanthropy, Hank wuuuuvs them and is desperate to win Karen back.

That's kind of it. Except that, every woman who meets Hank instantly wants to have sex with him. Seriously, I was convinced I was watching a bad joke adaptation of the script Patrick Stewart was writing in Extras. Every time he sees a woman, all her clothes fall off.

Studio 60 was criticised for being solipsistic, but the self-absorption here is of black hole proportions. With its anti-hero wandering around drinking, screwing, smoking, dressing in black, wearing shades and feeling sorry for himself (but with a heart of gold, if only you'd dig for it), Californication is either like a 15-year-old boy's idea of sexy and moody, or a crisis-struck middle-aged man's. You wait for irony to kick in. It doesn't.

People keep telling Hank he's a complete jerk, but none really mean it. The show's creator, Tom Kapinos, is most sincere when he has other characters praise Tom's - er, I mean Hank's - "incredible talent" or tell him things like, "You're a real writer, a real man, you've got heart and balls". Thing is, the programme still just about gets by, because it calculates, correctly, that Duchovny has such sly, sleepy charm you can't help liking him. Still, if his character continues to love himself to the same degree, that could wear off.

There's lots to love, though, about the sitcom 30 Rock, named by its creator Tina Fey after 30 Rockefeller Plaza, New York City's Art Deco TV temple. Fey stars as Liz Lemon, head writer on a live comedy sketch show, whose programme's equilibrium is unbalanced by the arrival of a new head of production, Jim Donaghy, played by Alec Baldwin like an alligator trying to pass as human by disguising himself as a bear in a suit.

Baldwin is a curious one. He's famous, but he's also seriously underrated. He gives full vent to his essential, devious, mighty inner weirdness here and the programme begins to spark, click and bristle with him.

30 Rock should be on a hiding to nothing as, of all the shows modelled on the untouchable Larry Sanders, it comes closest to aping it. But it swiftly forges its own personality around Fey, who manages to be everywhere, yet disarmingly modest about it. Her style is classic screwball - fast, sharp, sophisticated and witty, but not afraid to get its hands dirty with stupidity and slapstick. She had me halfway through the second episode, anyway, when her writers started throwing things at her and covered her in what looked like mayonnaise.