Premiere Week. CBS has three "CSI's." CBS wins. Get used to this, because you're going to see a lot more weeks like it this season.

Here's a look at the week's winners and losers:

WINNERS

All things "CSI." CBS's Jerry Bruckheimer crime-drama franchise accounted for three of Premiere Week's top five programs. On Thursday, nearly 31 million viewers caught the fifth-season debut of the show that started it all -- its biggest opening audience ever. "CSI" was the week's No. 1-ranked program, beating its time-slot competition on ABC, NBC and Fox combined. "CSI: NY" handily beat NBC's "Law & Order" at 10 p.m. Wednesday and is the most watched new series premiere of the season to date, averaging 19.3 million viewers. Even "CSI: Miami" had a good week, opening its season with 23 million viewers -- about 5 million more than its 2003 debut -- no doubt thanks to the killing off of one of its stars on Monday.

Barbara Walters/Mary Kay Letourneau. Did 11 million viewers tune in to "20/20" on Friday because it was Walters's swan song as host, or because she was going to interview child seducer Letourneau? We have our suspicions but, anyway, the season debut drew 3 million more viewers than last season's, was the most watched newsmag of Premiere Week and in its time slot beat by nearly 1.7 million viewers poor Rob Lowe's latest stab at TV stardom, the premiere of CBS's "dr. vegas."

"Lost." Has ABC lost its unerring instinct for buying drama series no one wants to watch? Nearly 19 million viewers tuned in Wednesday at 8 p.m. to watch the unveiling of this goofy drama about a bunch of 18-to-34-year-olds who survive a plane crash on a tropical island inhabited by a Really Big Scary Monster. It was ABC's most watched drama premiere since 1995 and landed in Premiere Week's top 10 list.

"Without a Trace." Nearly 30 percent of its "CSI" lead-in audience vanished without a trace. Still, this CBS series was left with nearly 22 million viewers, enough to become the first drama series to beat an original episode of "ER" in head-to-head competition.

"ER." While "Without a Trace" was busy fumbling more than 9 million "CSI" viewers, NBC's 11-season-old doc melodrama was adding 4 million viewers to its lead-in audience, for a total of about 20 million. End result: "WOAT" edged out "ER" by only about 2 million people although it headed into the Thursday 10 p.m. hour with a 15-million-viewer advantage. "ER" also managed to beat "WAT" among 18-to-49-year-olds, whom advertisers covet -- and did we mention that "WAT" is eight years younger than "ER"?

LOSERS

Shannen Doherty. Fox added Miss Congeniality to the cast of "North Shore" last Monday and yet the prime-time soap plunged to its smallest audience ever -- 4.1 million viewers. Miss Doherty apparently is no Heather Locklear.

Heather Locklear. On the other hand, Heather Locklear is no Heather Locklear these days either. Her new NBC series, "LAX," nosedived last Monday, winding up with just 7.9 million viewers, compared with the previous week's premiere crowd of 13 million.

"The OC: Day in the Life." A really bad day, apparently. Only 2.7 million people fell for this "OC" Thursday night "special," compared with the 3.3 million who'd fallen for an "OC" "special" the previous Thursday. Because you can fool all of the "OC" fans some of the time and you can fool some of the "OC" fans all of the time, but you can't fool many "OC" fans into watching clip jobs on Thursday when there's a new "Survivor" on.

"That '70s Show." As this Fox sitcom staggers toward the '80s and its stars look increasingly too old for their roles, especially those who are dating women in their forties, viewers appear to be losing their appetite for it. Last week it logged just 5.6 million viewers -- its smallest audience ever for an original episode.

The top 10 shows for the week were: CBS's "CSI," "CSI: Miami" and "Without a Trace"; NBC's "ER"; CBS's "CSI: NY" and "Survivor: Vanuatu"; NBC's "Law & Order"; ABC's "Monday Night Football" and "Lost"; and CBS's "Everybody Loves Raymond."