It takes an awfully long time to get Martha behind bars in ''Martha Behind Bars," which premieres tomorrow night at 9 on Channel 4. And that's a bad thing. Until she's in the federal clink known as Camp Cupcake, this silly TV biopic is not just another silly biopic. It's a boring prison-sentence of a silly biopic. The endless first hour ambles through a court battle whose outcome is old news, and it fudges enough detail along the way to make Martha Stewart's innocence or guilt just so much filler on the way to her fabulous martyrdom.
But once Stewart (Cybill Shepherd) is mixing it up with the tough gals in her cement cellblock, the movie at least lets some camp flow. And that's a good thing. ''Martha Behind Bars" becomes Martha as Maria in ''The Sound of Music," teaching the incarcerated kids with bad teeth how to make suspended origami cranes for Christmas. ''You skipped a loop on your cross-stitch," she helpfully advises one fellow con who's knitting, around the same time that she gets busted for holding contraband such as eggs and a fine nutmeg. When she leaves jail after five months (for another five months of house arrest), her cellmates give her teary hugs, good wishes, and a ragged but lovingly made poncho.
The appetite for more TV Martha may be waning, as evidenced by the poor ratings for this week's premiere of ''The Apprentice: Martha Stewart." And that may be because after years of real Martha scandal and a deluge of tabloid coverage, the TV Martha is of far less interest. She's even uncompelling in heightened form -- and Shepherd, who also played Stewart in ''Martha, Inc.," certainly goes for heightened. It's the Ben Affleck phenomenon. The guy can sell magazines like crazy, but he doesn't necessarily bring audiences to the box office for his paid work.
It's no longer fresh or funny to goof on Martha's mania for correct living, and it hasn't been for a long time. The jokes were already cliches when comedians began imagining her making over her prison cell. Too many times in ''Martha Behind Bars," we see the icon going through these fanatical motions once again, taking refuge from reality in her blinding passion for frivolousness -- just as she did with her famous ''focus on my salad" comment on ''The Early Show."
For example, after briefly denying wrongdoing at a restaurant with her daughter, Lexi (Sabine Singh), she rushes to say, ''Oh, we must try the lamb here, it's excellent." To her stockbroker, Peter Bacanovic (Gale Harold) she notes, ''Of course we did nothing wrong. Now here, have some more fresh papaya juice. It's good for you." OK, we already know that the lady is steely, and that she uses superficialities as a mask. And we know Shepherd enjoys playing her with veiled fury. So tell us something new, as Martha might say, or else wait politely with your mouth closed and your hands folded.
Matthew Gilbert can be reached at email@example.com.