Revealed his true colors - Idioms by The Free Dictionary
reveal (one's) (true) colors (redirected from revealed his true colors)
reveal (one's) (true) colors
To reveal what one really believes, thinks, or wants; to act in accordance with one's real personality, character, or disposition. Primarily heard in US. Dave said all along that he only wanted this deal because it was in the company's best interest, but he revealed his true colors once he realized that he wouldn't get any special commission for his efforts. It's only in times of crisis that your friends will really reveal their colors.
References in periodicals archive
General Allen revealed his true colors
when he said that Bashar al-Assad has lost all legitimacy to govern and that is incredibly arrogant statement for General Allen to make on behalf of the United States' government," he added.
Nasrallah revealed his true colors
and adopted the theory of being the ally of tyrant Bashar Assad.
This includes a noted Palestinian Arab columnist who has revealed his true colors
in an article for Arab media.