Related Clues:

• Say you're interested in catalogue
• Put your name down to go in
• Nominally commit oneself to work?
• Become part of, as a cult
• Often-pressed key
• Boy tries out record
• With 23-Across, sign, as a contract
• Get past the gate
• "The door's open!"
• Agree to join
• Key with an arrow
• Record of inflammation it is not
• Knock response
• "It's open!"
• Go in, as a building