David Letterman's 10 Most Memorable 'Late Show' Moments (Video)

The late-night veteran will sign off in 2015; THR highlights some of Letterman's best "Late Show" chats.
John Paul Filo/CBS
Joaquin Phoenix and David Letterman in 2009

Late Show's David Letterman is retiring in 2015.

“The man who owns this network, Leslie Moonves, he and I have had a relationship for years and years and years, and we have had this conversation in the past, and we agreed that we would work together on this circumstance and the timing of this circumstance," Letterman said on Thursday's show in announcing the news. "I phoned him just before the program, and I said ‘Leslie, it’s been great, you’ve been great, and the network has been great, but I’m retiring.' ”

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Since Letterman began his Late Show run in 1993 at CBS, after a 10-year stint at NBC's Late Night, Letterman has filmed more than 4,000 episodes. The Hollywood Reporter highlights 10 of Letterman's most memorable interviews and moments on the CBS late-night talk show.

First Post-9/11 Show on Sept. 17, 2001

Letterman was one of the first comedy titans to return to the air following the Sept. 11 attacks in New York City. In his opening monologue, which was devoid of the show's usual theme, an emotional Letterman tried to understand the intent behind the attacks before praising then-Mayor Rudy Giuliani and the police and fire departments. "If you didn't believe it before, you can absolutely believe it now. New York City is the greatest city in the world," Letterman said. The tagline would also change following the Sept. 11 attacks, labeling New York City as "The greatest city in the world!" His guests that episode were CBS newsman Dan Rather, who broke down several times during the interview, and Letterman's friend Regis Philbin.

Joaquin Phoenix on Feb. 11, 2009

An unshaven Phoenix, donning shades inside the legendary Ed Sullivan Theater, dropped by the Late Show in 2009 for what would turn out to be a bizarre interview with Letterman. It was during the awkward 10-minute chat that the actor announced his retirement from acting to start a rap career. Phoenix would later apologize for his antics in a 2010 return appearance. (I'm Not Here director Casey Affleck would explain that Phoenix's bizarre Late Show interview was all part of the film.)

Drew Barrymore on April 12, 1995

Barrymore made heads turn when she jumped on Letterman's desk and unexpectedly flashed Letterman after finding out that it was his birthday. Courtney Love would pay homage to Barrymore's interview by doing exactly the same thing nearly a decade later on March 17, 2004.

Madonna on March 31, 1994

The Queen of Pop's famous chat with Letterman had Madonna swearing more than a dozen times and had the singer call the late-night host a "sick f---" after he asked her to kiss an audience member. The heavily censored interview was also one of Late Show's highest-rated and afterward, Madonna would not return as a regular guest until 2000.

Warren Zevon on Oct. 30, 2002

The musician was a featured guest for the entire episode, which came after he was diagnosed with terminal peritoneal mesothelioma. Zevon discussed at length his cancer diagnosis and when Letterman -- who has provided background vocals on several of Zevon's songs -- asked what he knew now about life and death, he replied: "Enjoy every sandwich." He also made his last public performance on Late Show, singing "Roland the Headless Thompson Gunner." Less than a year later, Zevon died.

Borat on Oct. 30, 2006

Sacha Baron Cohen did the interview in character as Borat as part of his publicity round ahead of the 2006 comedy feature, where he celebrated his young "wife's" death and declared that he enjoyed watching women "make the toilet." To say Letterman looked uncomfortable was an understatement.

Bill Murray on Aug. 30, 1993

Letterman's very first guest at the start of his 22-year run as host of the Late Show was Murray, who had also served as his first Late Night interview. Murray pray-painted "Dave!" in front of his desk. Murray has been interviewed more than two dozen times by Letterman.

Lady Gaga in May 17, 2011

Lady Gaga made a lasting impression in one of the more bizarre recent chats. Dressed in a get-up only the ARTPOP singer could pull off, Gaga was visibly fed up with Letterman's questions regarding the various rumors, prompting her to rip up the piece of paper, balling it up and proceeding to eat it. "That's not what you think... It's chemically treated. You're going to be sick for weeks," Letterman said to Gaga.

John McCain's No-Show on Sept. 24, 2008

McCain announced his presidential run on Late Show six months prior to his scheduled September 2008 appearance, but he failed to show up at the last minute for a pre-scheduled chat. McCain's excuse? That he was enroute to Washington D.C. to help draft a proposal for a ballot. When that turned out to be a lie -- Letterman broadcast an internal feed with McCain getting ready for an interview with Katie Couric -- he became understandably more upset. McCain would appear on Oct. 16.

Johnny Carson Tribute on Jan. 31, 2005

Letterman paid tribute to his mentor Johnny Carson in his first Late Show following Carson's death. Guests that hour were Tonight Show Starring Johnny Carson executive producer Peter Lassally and orchestra leader Doc Severinsen.