Buffy The Vampire Slayer

The commercial broadcast networks are major-league believers in that old saying about all things old being new again. That’s why each fall, they throw some fresh twists into returning series, hoping to keep formula-driven concepts from turning stale.

Sometimes it’s because shows are starting to display signs of age. Sometimes it’s because stars defected from a program or were fired. Sometimes it’s to boost the viewership for a series with stagnant ratings. And sometimes a new producer brings a different tone to an established hit.

All of these reasons come into play on NBC’s "The West Wing." It was looking a little creaky last season. It has a departing star (Rob Lowe moving into the Peacock Network’s new drama "The Lyon’s Den"). It will be adding new cast members in an attempt to juice ratings.

And, yes, there’s a new producer in charge. John Wells has been sworn in as the White House drama’s new chief executive, assuming increased duties now that two of the acclaimed series’ co-creators, writer Aaron Sorkin and producer-director Tommy Schlamme, have left.

Wells is expected to take "The West Wing" in a slightly different direction, changing the pace and the tone. Look for more character development and less emphasis on the biting-banter stuff that was a Sorkin specialty. Also look for Annabeth Gish (who played agent Monica Reyes on "The X-Files") as President Bartlet’s eldest daughter and Steven Eckholdt (the husband in last season’s "My Big Fat Greek Life") as her husband.

Joining the Bartlet Bunch as a semiregular will be Gary Cole, who played Mike Brady in the "Brady Bunch" movies. He’ll make his "West Wing" debut in this season’s third episode, cast as the new vice president, Robert "Bingo Bob" Russell of Colorado.

Another much-praised drama facing sweeping changes is ABC’s "The Practice." Given a financial ultimatum by the network, creator and executive producer David E. Kelley has dismissed top-billed Dylan McDermott, along with series regulars Lara Flynn Boyle, Kelli Williams, Lisa Gay Hamilton and Marla Sokoloff. Joining returning regulars Camryn Manheim, Steve Harris, Michael Badalucco and Jessica Capshaw will be new cast members James Spader, playing ethically challenged lawyer Alan Shore, and Rhona Mitra, playing tough paralegal Tara Wilson. Sharon Stone will appear as a client in three episodes.

New cast members are also the prescription for renewed health at NBC’s "ER," where Linda Cardellini ("Scooby-Doo," "Freaks and Geeks") will take up residence as Samantha Taggart, a nurse and spirited single mother. She’ll start in late October, about the same time comedian Bob Newhart will check into the hospital for three episodes as an architect suffering from macular degeneration.

And how’s this for really big changes on the drama front? When Fox’s real-time spy thriller, "24," begins its third season Oct. 28, the story will have jumped more than two years into the future, and Jack Bauer (Kiefer Sutherland) already will be on the trail of a new villain. Joining the cast are Wendy Crewson as Dr. Anne Packard and DB Woodside (Sunnydale High’s principal on "Buffy the Vampire Slayer") as the new White House chief of staff. Other new regulars include Agnes Bruckner and Zachary Quinto. James Marsters’ 123-year-old vampire, Spike, last seen consumed by fire in the series finale for "Buffy the Vampire Slayer," will try to ignite new interest in the WB’s nearly canceled "Angel." Spike gets a new lease on undead life when Marsters brings fresh blood to the "Buffy" spinoff, which begins its fifth season Oct. 1. Gone from the revamped vampire show are Charisma Carpenter’s Cordelia Chase and Vincent Kartheiser’s Connor. But Mercedes McNab, another "Buffy" refugee, will show up on "Angel" as Harmony.

Other new faces to be looking for in prime time this season:

Sofia Milos joins the cast of "CSI: Miami." She begins investigating crime scenes as detective Yelina Salas when the CBS drama launches its second season tomorrow night.

Jacqueline Torres, who appeared in the first four episodes of "Hack" as ever-positive ex-nun Liza Garza, becomes a regular on the CBS crime drama starring David Morse.

Greg Grunberg joins the cast of ABC’s "Alias" as agent Eric Weiss. And Melissa George will begin playing Lauren Reed, super-spy Sydney’s rival for Vaughn’s affections, in the second episode of the espionage thriller’s third season.

Lisa Guerrero is the new sideline reporter on ABC’s "Monday Night Football."

But on a far more serious note, however, the returning show now faced with the most daunting challenge of all is ABC’s tragedy-stricken "8 Simple Rules for Dating My Teenage Daughter." Can it continue without top-billed star John Ritter, who died Sept. 11 of a heart ailment?

ABC programmers will give it a try, even though prime-time history is overwhelmingly against them. Network executives announced last week that they would not recast the role played by Ritter, preferring to write the character’s death into the story line and add new regulars later in the second season. The three episodes Ritter completed will begin airing Tuesday night.

But the sad truth is that viewers have a difficult time sticking with a situation comedy reeling from the death of a major star. They didn’t when Redd Foxx died of a massive heart attack less than a month after "The Royal Family" premiered in 1991. And they didn’t when "Chico and the Man" tried to go on after Freddie Prinze’s suicide in 1977.

It’s difficult to get over this big of a loss, which is not a criticism of the audience or the people behind "8 Rules." It’s a testament to how much a performer such as Ritter meant to viewers and to this show.