LOS ANGELES - The "CSI" investigators spent much of last season hunting down a serial killer. Now they're after an equally elusive target: a sense of humor.

The former No. 1 drama has a new night and a new lead in Emmy winner Ted Danson, who takes over for a grim Laurence Fishburne. Most important, there's a new tone, a welcome change for the veteran cast.

"I had a hard time going to sleep last night, because I was so excited about coming to work, and it's been a while since I've been that excited to be here," said George Eads, who has played Nick Stokes since the show premiered in 2000. "We got so dramatic for so long that it seemed every scene I was doing up there was fire and brimstone. It's a different feeling than it's been in years."

Audiences seem to be craving a new direction. The show peaked during the 2002-03 season, attracting more than 26 million viewers a week. Last year, it averaged half that number and finished 12th in the ratings.

Enter Danson. Fans once had a problem disassociating the actor from his "Cheers" character until he got them back with hilarious turns on "Curb Your Enthusiasm" and more dramatic ones on "Damages."

But his new character, D.B. Russell, might have more in common with Sam Malone than viewers might think.

"He's kind of like Phil Jackson coming in to handle a group of incredibly bright people that are on a slippery slope, and that rings a bell with me," said Danson, 63. "Trying to hold together a crazy group of people, whether they're crazy-bright or crazy-silly, is something I've done before and that I kind of respond to."

Unlike Malone, Russell isn't a skirt-chasing egomaniac. He's a devoted husband whose wife interrupts him at work to ask about the nearest farmers market. He has four children, which might explain his rapport in the first episode with a young, shy witness, using a magic trick and patience to unlatch crucial information. Instead of being a recluse, like the characters played by former leads William Petersen and Fishburne, he offers to treat the CSI staff to breakfast and refers to them as "family."

"The joke, traditionally, is that if you have sex on 'CSI,' you die," said co-executive producer Don McGill. "Ted's character has had sex at least four times, as far as I know."

Danson's light touch doesn't mean the show is abandoning bloody, bizarre murders and a steady stream of corpses. In the season premiere, the team investigates a club that caters to men who like to see women have sex with an octopus. Next week, they try to figure out who wiped out an entire family.

But don't think Danson can't handle the serious stuff. Yes, he's a sitcom staple, but he also turned in a haunting performance in the 1994 incest-themed TV movie "Something About Amelia" and showed up in 1998's "Saving Private Ryan." He even played a detective in 1979's "The Onion Field."

But perhaps the best preparation for the new gig comes from the fact that his father was an Arizona archaeologist. Danson recalls finding a human skull in the woods when he was 11. Instead of bringing it home, he and his friends decided to play Romans and Gauls, then abandoned the find. His father was furious. Five years later, a friend rediscovered the skull and the missing person was finally identified.

"That's my little CSI story," Danson said. "Isn't it cool?"