New cast members rejuvenate old premises

If it ain’t broke, don’t fix it. That seems to be the motto for many returning hit shows this fall. While there are a few cast changes here and there to spice things up, the major plot twists are saved for the November and May sweeps periods, or the producers aren’t willing to spill the beans yet.

Here are a few preseason nuggets that tight-lipped execs were willing to share:

  • Following in the footsteps of Lucy and Ethel, Doris Roberts, everybody’s favorite mother figure, will be traveling to Italy to get back in touch with her roots on “Everybody Loves Raymond.”

  • When we last left Noah Wyle’s Dr. Carter on “ER,” he was heading for a rehab program to get over his addiction to painkillers. Viewers will get to see how he’s handling his troubles, but there won’t be any new cast regulars.The first guest star to be announced for the new season is Oscar winner Sally Field, who will appear in six episodes as Maura Tierney’s mom.

  • Over at “The West Wing,” the Peacock’s Wednesday-night hit, Janel Moloney, who plays Bradley Whitford’s assistant, has been granted full-time status, while Moira Kelly has been handed her marching papers.

    Of immediate concern, however, are the ramifications of the assassination attempt of President Bartlett during last year’s season finale. Bodies were shown strewn across the pavement but it’s not known who was actually hit with flying bullets. There will also be an episode detailing how the prexy’s staff got together.

  • The revolving casting door continues to spin at “Law & Order,” where two-time Oscar winner Dianne Wiest comes aboard as a new district attorney, replacing Stephen Hill, who has been on the case for the past 10 years.

  • Two other casting notes for NBC: Shelley Morrison (Rosario) will have a permanent role on “Will & Grace” and Ice-T will be a new detective on “Law & Order: Special Victims Unit.”

  • On the Alphabet web, the biggest news is that Charlie Sheen takes over for Michael J. Fox on “Spin City.” Sheen’s arrival is just one of many moves on “Spin.” Connie Britton, Alexander Gaberman and Victoria Dillard will all be written out as the mayor’s gang tries to figure out how to move on with deputy mayor Fox no longer calling the shots. It’s expected that Sheen will take over as the new deputy mayor.

  • Over at “NYPD Blue,” James McDaniel is stepping down as Lt. Arthur Fancy. He won’t be leaving until the 14th episode of the season, but this marks another departure for the men and women of New York’s finest. Andrea Thompson has also left the show to become a news anchor in Albuquerque, N.M.

  • Faith Ford, who worked regularly on “Murphy Brown” several years back, is returning as a series regular on “Norm,” playing Norm Macdonald’s girlfriend.

  • At CBS, Vivica J. Fox is gone from “City of Angels,” Yasmine Bleeth has departed “Nash Bridges” to work on NBC’s Aaron Spelling sudser “Titans” and Tony Danza is the new man in town on “Family Law.”

  • After much debate, it’s been confirmed that David Duchovny will appear in 11 episodes of Fox’s “The X Files” throughout the season and the show will introduce Robert Patrick (“Terminator 2″) — seen most recently as a degenerate gambler on “The Sopranos” — as Gillian Anderson’s new partner in crime fighting.

  • Robert Downey Jr. will be leaving his legal trouble behind when he pops up as the new attorney in Calista Flockhart’s life on “Ally McBeal.”

  • And the big news, of course, at the WB is how Keri Russell’s hair will look for her third year on “Felicity.” After a misguided shearing that had both auds and critics scratching their heads, Russell will no longer be follicly challenged and is ready to take on books and boys, with a lovely new mane.
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