Comedian David Letterman apologized to his wife and staff Monday during his first show since police arrested a CBS producer for allegedly trying to blackmail him.

During his opening monologue, Letterman made fun of the revelation that he slept with members of his staff.

"I got into the car this morning and the navigation lady wasn't speaking to me," he joked.

But guests at the Ed Sullivan Theater say he turned serious later in the show.

"My wife Regina, she has been horribly hurt by my behavior. And when something happens like that, if you hurt a person and it's your responsibility, you try to fix it," said Letterman. "And at that point, there's only two things that can happen, either you're going to make some progress and get it fixed or you're gonna fall short and perhaps not get it fixed, and let me tell you folks, I've got my work cut out for me."

Those in attendance said they appreciated the apologies.

"He made an apology to first his wife and second to other females. I didn't quite understand the context of apologizing to other females on the show that may have been implicated as I guess you know partners," said one "Late Show" audience member.

"He made some comments that were on one hand very apropos and also funny at his own expense. He expressed his concern as far as the staff which he said he hadn't mentioned before he hadn't thought how difficult it would be for them," said another "Late Show" audience member.

Last week, Robert "Joe" Halderman pleaded not guilty to attempted grand larceny and was released after posting $200,000 bail.

Halderman, a producer for the CBS show "48 Hours Mystery," allegedly copied parts of his ex-girlfriend's diary where she wrote about sex with Letterman. Authorities say Halderman tried to extort $2 million.

Letterman testified before a grand jury and admitted the affairs on his show last Thursday.

If convicted, Halderman faces five to 15 years in prison.