The recent death of Rue McClanahan reminds me that she played opposite two different actors on three different TV shows:
Rue McClanahan & Bea Arthur–Maude & The Golden Girls
Rue McClanahan & Betty White–Mama’s Family & The Golden Girls
The other three sets of actors I could think of:
Fran Drescher & Charles Shaughnessy: The Nanny & Life with Fran
Bill Cosby & Phylicia Rashād : The Cosby Show & Cos
Johnny Galecki & Sara Gilbert: Roseanne & The Big Bang Theory
Note: Gyest stars do not count. The actor must play at least a recurring role.
Edie Falco and Paul Schulze have been in more than one episode each in The Sopranos and Nurse Jackie and perhaps Oz and at least one movie.
Courteney Cox & Christa Miller: Scrubs & Cougar Town
Sonya Walger & Dominic Monaghan: Lost & FlashForward
Practically the entire casts of Oz and Law and Order: SVU
Lucille Ball and Gale Gordon – The Lucy Show and Here’s Lucy
Lucille Ball and Vivian Vance – I Love Lucy and The Lucy Show
Peter Lind Hayes and Mary Healy – The Peter Lind Hayes Show and Peter Loves Mary (It helped that they were married)
Tim Conway and Joe Flynn – McHale’s Navy, The Tim Conway Show
Lucille Ball & Vivian Vance were on I Love Lucy and The Lucy Show.
Lucille Ball and Vivian Vance on I Love Lucy and The Lucy Show, and Lucille Ball and Gale Gordon on The Lucy Show, Here’s Lucy, and Life with Lucy.
Edit: Geez! Beaten to the punch by somebody else beaten to the punch; that stings.
Gale Gordon was a regular on Lucille Ball’s The Lucy Show and Here’s Lucy (he was essentially playing the same character with a different name). According to IMDb, he was a regular, guest star, or co-star on five series with Lucille Ball (if you count the Lucy-Desi Comedy Hour as a separate series).
typoink: I know the feeling.
Would you count the various versions of Mayberry as separate shows? If so, Andy, Don, Ronnie and a batch of others can make the list.
Then there was Lucille Ball and Vivian Vance. Let’s not forget them.
This may be cheating a bit, but Ron Howard, Henry Winkler, and Scott Baio were all on Happy Days and Arrested Development.
This is a spinoff case, but still:
David Boreanaz, Charisma Carpenter, Alexis Denisof: Buffy the Vampire Slayer and ‘Angel’
OK, Tom Poston had a recurring role (5 episodes) as Bob’s college buddy on The Bob Newhart Show before being cast as a regular (the dimwitted handyman) on Newhart.
Well, if we’re allowed to cross genres, Tina Fey and Tracy Morgan.
Do mini-series count? If so:
Mary Louise Parker and Justin Kirk: “Weeds” and “Angels In America”
Oh, I’ve remembered more - the whole Sorkin cast of regulars:
Evan Handler, Matthew Perry and Bradley Whitford: “The West Wing” and “Studio 60 on the Sunset Strip”
Mary McCormack, Josh Malina, Allison Janney: “The West Wing” and “In Plain Sight”
Josh Malina and Teri Polo: “Sports Night” and “The West Wing” (I would include Lisa Edelstein, but her character was gone by the time Malina joined the cast, so they never played opposite each other.)
They can go one more. Poston also had a recurring role on Newhart’s later, less successful series,* Bob*.
How about Tim Conway & Ernest Borgnine (“McHale’s Navy” & “Spongebob”)?
Martin Landau and Barbara Bain - Mission: Impossible and Space: 1999. They’d only do shows with colons.
Michael Hogan and Tahmoh Penikett of *Battlestar Galactica *had both been regulars on Cold Squad, but not in the same seasons.
Show and a movie - Goodfellas and the Sopranos:
Lorraine Bracco, Michael Imperoli and Frank Vincent.
Ben Browder and Claudia Black on Farscape and Stargate: SG-1