show your true colours

show (one's) (true) colours

To reveal what one really believes, thinks, or wants; to act in accordance with one's real personality, character, or disposition. Primarily heard in UK. Dave said all along that he only wanted this deal because it was in the company's best interest, but he showed his true colours once he realised that he wouldn't get any special commission for his efforts. It's only in times of crisis that your friends will really show their colours.
See also: colour, show

show your true colours

COMMON If someone shows their true colours, they show their real character, often when this is bad. Note: A ship's colours are its national flag. Someone I had trusted now showed her true colours. Note: Verbs such as declare and reveal are sometimes used instead of show. Three months into the relationship, Rogers began to reveal his true colours. Note: You can also see someone in their true colours. The children started seeing him in his true colours for the first. Note: Once a pirate ship had got close to a treasure ship by `sailing under false colours', it then revealed its true identity by raising its own flag.
See also: colour, show, true
References in periodicals archive ?
Amnesty International Ireland and the Irish National Teachers' Organisation were among those in the Show Your True Colours themed event.
One chance to show your true colours Show your true colours and join The Football League's Arch to Arc bike ride in support of Help The Hospices, linking two of Europe's must iconic landmarks.
Football referee Howard Webb is urging people to join the bike ride, saying: 'Whichever club you support, or even if you just want to get fit, the Arch to Arc bike ride is a chance for you to show your true colours and unite around a common goal: supporting hospice care so more people with terminal and life-limiting illnesses can make every moment count.
Show your true colours this Christmas with Lancaster who present a limited edition Luxury Powder Compact (pounds 30), Lipstick (pounds 15) and Brush Set (pounds 35) all silver-plated for the best-dressed handbag, which should keep you glowing throughout the festive season.