Related Clues:

• Tour part
• Red alert?
• Couture collection
• "Don't take another step!"
• One of five in a limerick
• What 28-Across means
• Ticket window sight
• Checkout-counter backup
• "Don't I know you from somewhere?" e.g.
• Sign outside a post office
• "Hit the brakes!"
• Exclamation to a pesky sibling
• With 28-Across, like some traffic
• "Cut that out!"
• "Go no further!"