If loganamnosis is a mania to recall forgotten words, what's the word for one who's seeking a lost phrase/saying? whatever is it, i've got it...

can anyone remind me of the saying that means something vaguely along the lines of 'a wolf in sheep's clothing' but with a definite reference to the the fact that the wolf's identity is obvious? something in the back of my mind tells me there may be a reference along the lines of 'no matter how you dress up s*it(PMF)
it still stinks' (and thus will sooner or later be discovered)

it could be applied, for instance, to me tricking my toddlers into cleaning their rooms by making an 'exciting contest' out of it; it only works once or twice and then they see through the guise.

any ideas?