Related Clues:

• Call for assistance
• Desperate trio?
• Message frantically tapped out
• Mayday call
• Skipper's plea
• Help wanted sign?
• Only hit song for which title and artist are both palindromes
• An obvious cry for help
• Coded plea
• Sea call
• Morse code message
• Sinking signal
• Sign of distress
• Mayday! Mayday!
• Main message?