Not-thog is hurting my thinky spot.

[Killer Angel]

Read Terry Pratchett's Masquarade. It's one of the Discworld novels, this time about opera. He comments (in ways only Terry can) about the "disguises" used in opera. A single, tiny mask, no changes in clothing, but NOBODY can identify the person thus disguised.

Actually, read any and all Terry Pratchett books. Time well spent.

Another example is Superman. Remove the glasses, and Clark Kent is unrecognizable!