After David Letterman retires from late night, perhaps he’ll spend his free time fishing and catching up on all the novels he’s been meaning to read. Or maybe, just maybe, he’ll resurrect his acting career. Though Letterman has always preferred to appear as himself onscreen, over the years he has taken a handful of acting roles. As we near his Late Show farewell, let’s look back at a few times when, for better or worse, Dave wasn’t himself. 

1. MARY (1978)

Back when everybody and her cousin had a TV variety show, Mary Tyler Moore got into the game—and Letterman was hired to play one of her featured players. In this clip, Dave appears to be laughing his way through a cheesy musical number alongside now-famous cast mates Michael Keaton and Swoosie Kurtz. Despite the talented roster, CBS axed the program after three episodes.

2. PEEPING TIMES (1978) 

This TV special still holds up, largely because of contributions from Letterman, Mel Brooks, Barry Levinson, and Christopher Guest. Intended as a satire of newsmagazine programs, Peeping Times features Letterman as a roving reporter out to get the scoop on Bigfoot, illegal aliens, and other hot topics. 

3. MORK & MINDY (1979) 

Years before I secretly watched Late Night while my parents were sleeping, I got a glimpse of Letterman on this sitcom as a skeevy, medallion-wearing motivational speaker. Last year Letterman mentioned the appearance during his moving tribute to Robin Williams on the Late Show:

I can remember between the dress rehearsal and the actual taping of the show the director of the program, Howard Storm, comes up to me and he says, Well, you’ve been trying all week, so this is your last chance. So even to the detriment of the show, Robin was kind enough to invite me to come on because he thought, Why can’t I spread this around and have some of my friends share in my success?” 

4. OPEN ALL NIGHT (1981)

“Let’s say, for example, that you had hosted the Tonight Show …” Perhaps the most astounding thing about Letterman’s appearance on this short-lived sitcom is the dialogue is spoken a decade before the famous Tonight Show debacle with Jay Leno. (In the late ‘70s and early ‘80s, Letterman often guest-hosted Johnny Carson’s Tonight Show. In this scene, he’s referring to the cancellation of his pre-Late Night daytime talk show.) 

5. THE BUILDING (1993) 

Produced by Letterman’s production company, Worldwide Pants, The Building starred Bonnie Hunt and only lasted a handful of episodes. This scene features Letterman as a masked thief who fumbles his way through a porn-shop robbery. (Also in the scene is Ellen Albertini Dow, who died earlier this month at age 101.) After The Building ended, Worldwide Pants produced another vehicle for Hunt, who also guest-hosted for Dave in 2003 when he was down with shingles. 

6. CABIN BOY (1994)

For his theatrical debut, Letterman chose this comedy from frequent Late Night contributor Chris Elliott. When he hosted the Academy Awards in 1995, he even turned his tiny Cabin Boy spot into a lengthy sketch, getting huge stars like Paul Newman, Tom Hanks, Madonna, Albert Brooks, Martin Short, Jack Lemmon, and Alec Baldwin to recite his most memorable line from the film: “Would you like to buy a monkey?” 

7. BEAVIS AND BUTT-HEAD DO AMERICA (1996) 

“These guys are, always will be and cannot be anything but idiots,” Letterman said of Beavis and Butt-Head in 1994. “And I find that, for some reason, endlessly gratifying and satisfying to watch.” In the MTV duo’s big-screen adventure, Letterman voices a former Motley Crue roadie who—spoiler alert—turns out to be Butt-Head’s father. It was actually the second collaboration for the trio; in 1994 they appeared together during the 1994 MTV Video Music Awards. 

8. SPIN CITY (1998) 

“Kill me,” begs Letterman’s character to a drunken Mike Flaherty, played by Michael J. Fox. If Dave weren’t voicing a suicidal dog named Rags, the scene might’ve been somewhat poignant. Fox and Letterman go way back, of course; on the actor’s final Late Show appearance last month, they chuckled over Fox’s 1985 Late Night debut.