Heartfelt Thanks From Letterman

David Letterman believes in acknowledging those who have made his life good.

Several years ago, after a close call that required immediate heat bypass surgery, the CBS Late Show host returned to the airwaves with public thanks for each and every one of his doctors and nurses.

A week ago, the close call was also very near his heart - heart and hearth - as police arrested a painter who'd worked at Letterman's Montana home, accusing him of a plot to kidnap the entertainer's toddler son, Harry, and his nanny.

Monday night, as Letterman did his first show since the details of the alleged plot came to light, gratitude was way ahead of comedy on the show's priority list.

"Last week, my family and I were involved in a little legal activity, and fortunately everything turned out fine, but I want to just take a second here to thank some people," said Letterman.

He thanked two FBI agents, Teton County Sheriff George Anderson, county attorney Joe Coble "and the great people of Choteau, Montana.

"They have always made me and my family feel entirely welcome as though it were our home," said Letterman, "and that's how we think of it."

Kelly A. Frank, 43, who worked at the Letterman's ranch near Choteau, was arrested last week and charged with solicitation. Authorities say Frank planned to ask for $5 million in ransom, snatching the child and his nanny the next time Letterman - whose main home is in the New York area - next visited the 2,700-acre ranch along with the child's mother, Regina Lasko.

"The thought was to kidnap the nanny and the child so the nanny could take care of the child during this period of the kidnapping," said Mike Ferriter of the Montana Dept of Corrections, at the time of the arrest.

Ferriter said apparently confided his kidnap scheme to an acquaintance earlier this month.

According to an affidavit filed by Teton County Attorney Joe Coble, Frank had told the acquaintance that he knew Letterman and his family would be visiting their Montana home soon, and that Frank had a key to the house and knew which of the rooms was the child's.

The acquaintance contacted authorities Sunday, according to the affidavit. Sheriff George Anderson told the weekly Choteau Acantha newspaper that Frank was arrested the next morning at another area ranch where he was working.

Besides the felony solicitation charge, Frank is charged with felony theft for allegedly overcharging Letterman for painting, and a misdemeanor charge of obstruction for lying to an investigator about the alleged plot.

CBS News Correspondent Trish Regan reports Frank was convicted back in 1999 for holding his then girlfriend against her will.

Frank is jailed in neighboring Pondera County on $600,000 bail.

His father, Robert Frank, told the New York Daily News last week that he hoped the authorities had made a mistake.

"I didn't see this coming," the newspaper quoted Frank, 75, as saying. "I just can't imagine him even thinking like that. I don't think he'd ever seen Letterman in his life."

Letterman bought the ranch in 1999. In 2003, a black bear broke into the house twice and was captured and relocated when it came back a third time.

On Nov. 3, 2003, Lasko gave birth to the couple's son. The boy, Letterman's first child, was named after the comedian's late father, Harry Joseph Letterman.

For years, Letterman was targeted by a stalker who called herself "Mrs. David Letterman" and broke into his Connecticut house at least seven times.

Margaret Ray eventually pleaded guilty to breaking and entering. Diagnosed with schizophrenia, she served 10 months in prison and 14 months in a mental institution. In 1998, she committed suicide at age 46 by kneeling in front of a train.