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Could this have been an episode of Big John, Little John (produced by Brady Bunch creator Sherwood Schwarz)?
There was also two episodes of an early 80's sitcom called Joanie Loves Chachi starring Scott Baio (Charles In Charge), that guest starred Ross and Bosley, as it was a Spin-Off of Happy Days.
No, this was filmed way before the 80s. Definitely had an early/mid 70s vibe, besides the fact that Ross & Bosley looked younger than they did even in the early seasons of Happy Days. I think it may have been an Industrial film
made before any of them were famous.
Happy Days itself was a Spin-Off of Love American Style, maybe an episode of that?
Oh, according to the "Credited With" section of I Md B, Bosley and Ross didn't appear in anything together before Happy Days in 1974. And it seems the only other 70s option is The Love Boat.
You seem to be pretty certain of your memory—given that you saw this about 20 years ago, and only seem to have caught a brief glimpse of it through the window of a conference room when you were almost certainly thinking about something else. I think it is very possible that you have one or more details wrong.
Brady Bunch first aired in 1969, I'm sure the set didn't exist before it was shot. So if you are correct that it was shot on the Brady Bunch set, it can't have been before 1969. Robbie Rist was born in 1964, and wasn't added to the Brady Bunch cast until 1974, the same year Happy Days went on the air.
However, Robbie Rist, Tom Bosley, and Marion Cunningham all made appearances on "Love American Style". I can't verify if there was ever an episode with all three of them.
I kindof doubt it would be an "industrial", why would such a thing be set in a house and have a "family" and an anti-smoking message?
You are correct - I am pretty certain of my memory. Which is not to say I'm 100% correct, but things like "an episode of Joanie Loves Chachi" are so obviously wrong I don't even know where to begin. I'd already looked at IMDB and seen that before Happy Days Bosely & Ross aren't credited with being in anything together, but IMDB is known to have some incorrect and/or missing stuff. I'd think that some obscure industrial film would be likely to fly under the radar of anyone posting there.
Being an industrial was just a guess. What I do know for a stone cold fact (the problem with eyewitness testiomony notwithstanding) is that (a) it took place on The Brady Bunch set, (b) both Tom Bosely and Marian Ross were in it as major characters, if not the stars, and (c) it looked to be filmed in the early 1970s - which is when the Brady set would be available for use. I think (1) it was an anti-smoking film, or anti-smoking related and (2) Robbie Rist was in it. Maybe I'm wrong about Rist - perhaps it was Mike Lookinland and/or Susan Olsen (Bobby & Cindy from the Bunch).
Edited by randomsurferThis is what I have discovered. Neither Ross nor Bosley were in the segment of Love American Style that Robbie Rist was in. Bosley did NOT play Mr. Cunningham on Love American Style, although Ross did play Mrs. Cunningham. (I still don't know what Bosley did on Love American Style). It doesn't look like they used the Brady Bunch set for the "Love and the Happy Days" segments of Love American Style. I'm very much thinking that what you are looking for is NOT a "Love and the Happy Days" segment from "Love American Style", (Could it just possibly be a different segment of "Love American Style")
But there would have been a brief period where both Brady Bunch and Happy Days were in production. And both were ABC shows. It is possible that ABC could have had two of their stars make an anti-smoking PSA (or some other PSA, or even just an ad for ABC), using a set from another show. This would need to have been when they were shooting the 1974 tv season (Brady Bunch's last season, and Happy Days' first). So if Ross and Bosley were in it, they would have looked rather young if you had only seen them in later episodes of Happy Days.
Another possibility, could it have been a screen test? Since Bosley was not in the "Happy Days" segments of "Love American Style", they may have called him in to see how he worked on screen with Ross, and they would have just used any set they had available.
Just some thoughts.
KEVP
Edited by KEVPI've discovered a little more. Bosley's role on "Love American Style" was a voice for an animated segment that eventually became the animated series "Wait 'til Your Father Gets Home". An article on Wikipedia says that there was only ever ONE episode of "Love American Style" that had "Love and the Happy Days". I think it is becoming clearer that "Love American Style" is a dead end for this question.
Wow, you did a lot of research on this. Thanks, despite the fact that you didn't find it.
I know this thread is a number of years old, but I was wondering if you ever found a copy of Let’s Call It Quits?” Do you recall the library that had a copy? I’ve been searching for over a decade for a copy with no luck. The libraries I contacted don’t have any VHS copy’s anymore. They got rid of all their VHS tapes. Any help is greatly appreciated.

An anti-smoking short film - I think - which starred Marion Ross and Tom Bosley (possibly before they were on Happy Days together), which used the sets of The Brady Bunch as their house. Robbie Rist (the original Cousin Oliver) may have played their son.
I saw a bit of it sometime in the late 80s/early 90s when I was at a hospital picking up my mother from a meeting, and it was being shown in conference room nearby that had glass walls where a stop-smoking workshop was being held which is why I think it may have had something to do with that.
Edited by randomsurfer