Idol's Rat-Pack Style Cramped by NCIS?

Singing competition rules Tuesday ratings, but slips a bit opposite all-new, guest-star-populated crime show

That's life, as Frank Sinatra would've sung.

A Rat Pack-celebrating American Idol ruled Tuesday with 22.5 million viewers, per preliminary Nielsen estimates, but lost about 1.5 million fans from last week as NCIS returned with an all-new episode—not to mention Chris O'Donnell and LL Cool J.

Elsewhere in last night's ratings:

• At 9 p.m., The Mentalist (16.9 million) was even bigger than NCIS (16.3 million) was at 8 p.m. Still, the Chuck Wicks-eliminating Dancing With the Stars (14.3 million) held up OK, while Fringe (10.6 million) went even more mainstream.

• At 10 p.m., Law & Order: SVU (10.5 million) killed among adults 18-49. Earlier, the CW's Reaper (1.8 million) and 90210 (1.8 million) plain got killed.

• Counting down to its own finale, The Biggest Loser (9.4 million) scored its biggest audience in nearly three months, per NBC.

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