show (someone) in (their) true colours

to show what someone's real character is, especially when it is unpleasant.

By showing the terrorists in their true colours, the government hopes to undermine public support for them.

• have the last laugh
• have the last word
• have the luck of the devil
• have the makings of
• have the makings of something
• have the measure of
• have the measure of someone
• have the measure of something
• have the right of first refusal
• have the right to first refusal
• have the run of
• have the run of somewhere
• have the run of swh
• have the stomach for
• have the stomach for something
• have the time
• have the time of life
• have the time of your life
• have the upper hand
• have the weight of the world on shoulders
• have the weight of the world on your shoulders
• have the whip hand
• have the world at feet
• have the world at your feet
• have time