Related Clues:

• Turn blue, maybe
• Henna, for one
• Litmus, essentially
• Stuff in a robber-foiling pack
• Self-help author Wayne
• It may be red
• It changes locks
• Salon application
• Food additive
• Textile company purchase
• Indigo, for one
• Certain cloth worker
• Turn red, perhaps
• Just for Men, e.g.
• Spot remover?