The big question about expanding the CSI franchise to a fourth, fifth or even sixth series is this: Will the producers run out of Who songs before they run out of cities?

Rock legends The Who provide the signature licks for CSI (Who Are You?) and CSI: Miami (Won't Get Fooled Again). The surviving members of the group, Roger Daltrey and Pete Townsend, rocked CBS' "upfront" to advertisers in New York this past May.

Executive producer Anthony Zuiker told critics in Los Angeles this weekend that choosing a third Who anthem was a little trickier.

"We had four songs in contention," he said. Zuiker's choice was Behind Blue Eyes. Viacom/CBS top executive Les Moonves, obviously a Who fan himself, chose Baba O'Reilly.

"And I said, 'Yes sir,' " said Zuiker. "I'll be darned, that man is always right."

While the lyrics to Baba O'Reilly don't seem to fit a forensic crime series as well as the other two CSI songs (it's a spiritual love song), Zuiker feels there is some common ground. "We'll choose the appropriate lyrics," he said. Hey -- it has to work better than Squeeze Box.

CSI: NY, starring Gary Sinise and Melina Kanakaredes, premieres Sept. 22.