Pierre Hamel of the '75 OKC Blazers and pre-Kotter Gabe Kaplan.
(okay, it was my brother and me, but you see the resemblances, right?)
In this particular costume, I knocked on my grandma's door, my uncle answered--and didn't recognize me. I duly reported back to my mother that "Uncle Terry didn't know" who I was, so she sent me back and I just walked right in the house. My uncle hollered for his mom (my grandma) and Grandma proceeded to lecture me on the impropriety, bad manners, and dangers of walking into a stranger's house.
At that point I believe I started giggling...and then the jig was up.
We still make fun of Grandma for that...and for many, many other things.
I have no idea why Grandma doesn't like me.