Which film character played the villian in the play "New Rochelle"?

I couldn't figure out who played the villian. It wasn't little Willie, he played Mickey's son. It wasn't Mickey's friend, the one that annoyed Mickey by always talking about Annie, cause I saw him playing one of the other characters with a mustache. It wasn't the fat kid Boof, cause that would've been obvious. I wonder if it was one of the adults, cause when I got closer looks, it did not look like a kid under all that makeup, but again good acting makeup can really look convincing. That villian really was grotesque looking, I must say. I just cannot figure out who played him.