Doors Of Imperception

Topps was chugging along with all sorts of esoteric non-sports issues as the odometer rolled over from 1969 to 1970. This was about year four of an internal underground comix and pop-art influence on Woody Gelman's New Product Development Department (NPD) that was peppering the youth of America with wildly inventive offerings, one of which was an interactive set of 24 subjects called Funny Doors.

It's impossible to miss the connection from which Funny Doors were sprung, namely 1968's Laugh-In subsets of Knock-Knocks and, prosaically, Funny Doors.  These both featured a small, hinged piece or two that opened up to reveal a funny saying on the under-flap and also an illustration that peeked through.  Topps refined the concept a bit and came up with a pretty humorous set.  Here is a typical example:

You can see the hinges for each little door; slightly bending the card allowed the purchaser to pry them open with their thumb, thereby ensuring a form of limited self-destruction that Topps seemed to revel in.

The setup was ingenious, with the inside surface of the door sometimes offering a word or short phrase that related to the revealed illustration. 

When printed front-and-back, the card was folded over and then sealed by Topps. As you may have surmised if unfamiliar with the set, these measure 2 1/2" x 4 11/16".

I've not seen enough of these in fully opened form (my set is 100% unopened) to know if there was something on the backside of each door but based upon this stack o'proofs from an old Huggins & Scott auction, I'm going with only some having this little extra appended on there:

The wrapper almost says it all:

Note the 1969 commodity code.  It's possible the set was green-lit in 1969 and released in 1970 but that 423 product number could cement it in '69; more research is needed there. And I say "almost" as there was a surprise inside the pack, a checklist card!

Standard-sized, it would have bounced a round a bit in the pack.  It had instructions on the back:

Some original art has popped up over the years, it's pretty neat:

A tissue overlay is known for this piece, it has some of the "inside" line art still extant and glue spots where some fell off:

I can't swear I've seen a retail box for the set but surely one exists as cards from the set, while assuredly not easy, can be found and that wrapper shown above is post-test.