It's not unusual for new shows to he tinkering with their casts right up until the last moment as they try to improve their chance for survival. That's certainly the case with this fall's sitcoms. NBC's Cafe Americain signed on Marion Ross (Brooklyn Bridge). On ABC, Joe's Life just added Mary Page Keller (Baby Talk), and George recruited Sheryl Lee Ralph (It's a Living).

But I can't remember a year in which so many established shows made significant cast changes during the summer hiatus. When they return next month, CBS's Love & War will feature Annie Potts (Designing Women); Murphy Brown will have Scott Bakula (Quantum Leap). ABC's Hangin' with Mr. Cooper welcomes Nell Carter (Gimme a Break) and Raven-Symone (The Cosby Show). NBC has added Loni Anderson (WKRP) to Nurses and Estelle Getty (Golden Girls) and Marsha Warfield (Night Court) to Empty Nest. Whether all this retooling works: You'll be the judge.

The Disney Channel (Sun., Aug. 15, 9 p.m. ET)

A-

What NFL Films is to professional football, documentarian Bud Greenspan is to the Olympics: He doesn't so much chronicle sports as he mythologizes them. Here Greenspan turns his exalting eye to last summer's Games in Spain, focusing on personal, vivid vignettes.

There's British sprinter Derek Redmond, after tearing a hamstring in the 400-meter semifinals, agonizingly limping around the track with the help of his father, Jim, who came down out of the stands to escort his son to his symbolic finish. There's Moroccan distance runner Khalid Skah (who just recently set a new world record in the 2-mile) being jeered by the crowd in Barcelona, which felt that his victory in the 10,000-meter race came about because he and a teammate conspired to sandbag a Kenyan runner. (Skah's gold medal in fact was stripped from him, then reinstated.)

Greenspan is slightly handicapped by a lack of great camera access to the actual competition. But it's a testament to his heightened dramatic technique that often during his film you'll find your heart thumping even though, in many cases, you already know how the race turns out.

Showtime (Sun., Aug. 15, 10 p.m. ET)

Overall Grade: B

This six-part series is made up of half-hour mysteries, all homages to the film noir style of the '40s. Dark and hard-boiled, it is full of grifters, corrupt cops, dangerous dames and violent ends.

The project, which began airing on alternate Sundays at the beginning of August, has attracted big-ticket talent both in front of the camera—James Woods, Isabella Rossellini, Gary Old-man, among others—and behind it—Phil Joanou and Steven Soderbergh are among the directors.

This week's installment, "I'll Be Waiting," directed by Tom Hanks, is based on a Raymond Chandler story. It stars Bruno Kirby as a hotel dick fascinated by a beautiful, imperiled guest (Marg Helgenberger). Hanks employs clever shots, but his piece is less strikingly lit than other segments.

While the series is an interesting exercise in style, the stories, grim and lacking in surprise, tend to be more portentous than eventful. The best of the lot are September's "The Frightening Frammis," promisingly helmed by first-time director Tom Cruise, and the series finale, "Since I Don't Have You," set in 1948, in which Gary Busey plays a legman for both millionaire aviator Howard Hughes and gangster Mickey Cohen.

Fox (Mon., Aug. 16, 8 p.m. ET)

B-

Paul Reiser (Mad About You) plays a carefree musician reluctantly joining the corporate world. Before the first day is half over, Reiser and his cavalier attitude have managed to antagonize the central computer that controls all facets of the futuristic Manhattan skyscraper where he works. The machine resolves to "delete" this irritating human.

The thriller is smoothly rendered but light on the fright meter. About the scariest thing that happens is that the computer hears Reiser singing Creedence Clearwater's "Bad Moon Rising," so it traps him in an elevator and pipes in a calliope Muzak rendition of the song.

TNN (Mon., Aug. 16, 10 p.m. ET)

B-

Country singing star Lorrie Morgan makes her acting debut in what amounts to an extended music video. She plays an autoworker who returns to her small Tennessee hometown upon her father's death to take over his failing service station. Along the way, she gets a chance to drive a tow truck and sing a few songs.

The story is too skimpy and compressed to warrant the film's overwrought mood. But Morgan does a fine job of establishing presence and projecting emotion. This rookie already looks as good and acts as well as Joey Heatherton ever did. And the Merry Postman's daughter once had a pretty busy acting career.

This week's cover

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Saved by the Bell Reunion

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