Incognito: (Adverb) Of a person having one's true identity concealed.
If you're having trouble recognizing this strange woman seen here -- you may be shocked and astounded to learn that it is none other than Christina Aguilera, holding her ginger baby Max. Likewise, you'd probably have trouble recognizing this man
named Joe Maggard, who portrayed Ronald McDonald from the early 1990's until just last year.
It just goes to show how clown makeup can completely disguise a person's identity, which is probably why clown is such a popular occupation for serial killers.
Normal, painted Christina at the The Trump International Hotel & Tower last week: