Some people adopt excellent manners only to camouflage their real character.

Project : an individual or collaborative enterprise that is carefully planned to achieve a particular aim.
Hide : put or keep out of sight.
Misrepresent : give a false or misleading account of the nature of.
Reveal : make (previously unknown or secret information) known to others.
Camouflage : hide or disguise the presence of (a person, animal, or object) by means of camouflage.

Synonym of Camouflage is Hide