Possible Clues:

• Benefit from a disguise, it's said
• To no __: unsuccessfully
• A cover said to be of use
• Medal (informal)
• A disguise said to help
• Will this help to cover your face, by the sound of it?
• "St Teresa's birthplace?" By advancing an answer, give help here
• Help against area in trouble
• A traditional perk may be advantageous
• To benefit