Related Clues:

• Historically
• First section
• Twice from thrice
• Tale beginning?
• One less than twice
• First word of 'Shrek'
• First word of a fairy tale
• "___ Upon a Mattress"
• Miniseries opener
• First of a trilogy
• "__ I built a railroad ...": Depression song lyrics
• If ever
• Fairytale beginning
• ___ in a lifetime
• Novel opening