Related Clues:

• ABBA song
• 'Help wanted'
• International distress sig.
• Palindromic plea
• Coast Guard pickup
• Emergency broadcast
• Urgent letters
• ... --- …
• Mariner's 'Mayday!'
• Letters in the sand, perhaps
• Mariner's distress call
• Message from the Titanic
• Help-wanted letters
• Letters in the sand?
• Signal for help