By Ken Tucker
Updated October 10, 2003 at 04:00 AM EDT

When it comes to lawyer shows, I want to see junkyard dawgs. No way, I thought, was I going to be drawn in by The Lyon’s Den and its crusading courtroom avenger Rob Lowe, whose best actor’s trick is to make his granite jaw seem tremulous when he has to register high-minded emotion. (Lowe is so lightweight, his version of Gregory Peck’s jury-trial classic would have to be retitled ”To Kill a Moth.”)

By the third ”Den” episode, someone has already referred to Lowe’s Jack Turner as ”the most principled lawyer in this building.” (Lowe’s shameless reaction: smiling until his dimples cringe and murmuring a soft, aw-shucks ”Thank you.”) And here I thought from all the ”Practice” ads I’d seen that it was James Spader who’d be playing the new season’s smug twit lawyer.

But ”Den,” created by ”24” coexec producer-writer Remi Aubuchon with assists from exec producers including Brad Grey (”The Sopranos”) and Dan Sackheim (”Kingpin”), uses Lowe brilliantly — as a sap, a foil for the real action. While the actor who wanted more face time than he got on ”West Wing” preens, the show is up to wonderful no-good. Lowe’s Jack is the only decent man in a mammoth, corrupt D.C. firm filled with jackals high (”Traffic”’s James Pickens Jr. and ”Early Edition”’s Kyle Chandler are amoral, you know, LAWYERS) and low (Frances Fisher as Chandler’s deliciously evil secretary). Elizabeth Mitchell, wasted two years ago in the flop corrupt-TV-news show ”The Beast,” is perfect as a recovering-alcoholic attorney enlisted by Chandler’s Grant Rashton to discredit Jack. Suicide, bribery, sexual and political hanky-panky…all this, plus Rip Torn as Jack’s lizard-skinned senator father, who’s colluding with the firm on some magnitude of nefariousness that Satan would probably have to start a blog to fully explicate.

Indeed, the more melodramatic and nighttime-soapy ”Den” is, the better it becomes. Meanwhile, Lowe looks like he fervently believes he’s found a vehicle to win him an Emmy — as Best Good Boy.