Related Clues:

• Forewarning of submarine captain being sent back
• Sign on, receiving a note
• Warning captain, having dived, rejected
• Surfacing submariner's premonition
• Prophetic event
• A sign from John Galt
• Sign saying 'Ladies Only?'
• Sign literary character underwater is surfacing
• Room enough to contain Galt's warning
• Old soldiers writing on the wall
• Warning from engineering section
• Sign of old people
• Warning against involving your setter
• Sign that's displayed at hen party?
• Sign in bathroom — "engaged"