Talk show icon David Letterman made his triumphant return to late night TV with an appearance on Jimmy Kimmel Live! Tuesday (Sept. 27), where the 75-year-old discussed his interesting and complicated relationship with radio host Howard Stern.

The pair initially became friends while working in the same building, but when Stern began to insult Letterman as part of his bits, it put a strain on their relationship.

"In those days Howard was a shock jock. And I was always afraid of Howard, because I didn't want Howard to say unpleasant things about me… But he did," Letterman told host Jimmy Kimmel.

"I kept thinking to myself, He must not have any feelings of his own, because he would say hurtful things, and the more hurtful things he would say, the greater his audience would become," Letterman continued.

But the past is in the past as far as Letterman is concerned today.

"Over the years, Howard and I have spent some time together and I’ve gotten to know Howard and he was such a sweet man to apologize for intimidating me. I’ve gotten to know him as a completely different guy, and that’s the guy that I have really gotten to be friends with over the years," the former talk show host recalled.

"Howard Stern's Birthday Bash" Presented By SiriusXM, Produced By Howard Stern Productions - Inside
Theo Wargo, Getty Images

The Private Parts star previously apologized to the comedian in Letterman's Netflix series My Guest Needs No Introduction, and the two rekindled their friendship.

However, Letterman noted he only talks to Stern "about once a year" — and for him that's plenty. The last time they spoke "it was a mistake": Letterman thought Stern sent him an original painting as a gift, but it turned out to be just an accident.

"There's a beautiful painting, a watercolor, and so I text him right back. I said, ‘Wow, Howard, that's unbelievable’. And then when I get home I call him. And he says, ‘Oh, yeah, I sent that to you by mistake.’ So I love Howard. I just think arm's length may be the way to go here," Letterman joked.

Watch David Letterman's full interview here:

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