That's down from last year's premiere but still pretty darn big

Fast National ratings for Tuesday, Jan. 13, 2009

The return of "American Idol" catapulted FOX to the top of the ratings Tuesday, while it looks like CBS may have found another "Idol"-proof show to go with "NCIS."

FOX averaged a 15.8 rating/23 share for the night, comfortably beating CBS' 10.2/16. NBC was a distant third at 5.6/9. ABC, 3.7/6, came in fourth, while The CW came in at 1.2/2.

FOX completely dominated the adults 18-49, drawing an 11.6 rating and beating the combined total of the other four nets. CBS took second at 3.5, followed by NBC at 3.3. ABC averaged 2.3 and The CW 0.8.

The season eight premiere of "American Idol" scored a 14.5/22 for FOX at 8 p.m. "NCIS" did its usual strong business for CBS, earning an 11.3/17. "The Biggest Loser: Couples" (5.0/8) held up reasonably well for NBC. "Homeland Security USA" put ABC in fourth, while "90210" managed only a 1.5/2 for The CW.

"Idol" improved to 17.1/25 at 9 p.m. The premiere averaged just a shade over 30 million viewers, which is down about 10 percent from last year but still makes it the biggest non-sports broadcast of the season so far. "The Mentalist" held onto nearly all of its lead-in audience, scoring an 11.1/16. "The Biggest Loser" rose to 5.8/8 in its second hour. An hour of "Scrubs" got smacked by the "Idol" train, averaging a 2.8/4. "Privileged" finished the night for The CW.

CBS moved to the lead at 10 p.m. thanks to "Without a Trace," 8.0/13. "Law & Order: SVU" posted a 6.1/10 for NBC, and "Primetime: What Would You Do?" delivered a 4.6/8 for ABC.

Ratings information is taken from fast national data, which includes live and same-day DVR viewing. All numbers are preliminary and subject to change.