Possible Clues:

• Entrance from beneath a stage
• Do in a wild parrot for an opening on the stage perhaps
• Prado rot possibly found on stage
• Hidden entrance
• Hinged floor panel
• You'd like to think it lets actor down gently at corner exit
• Hidden exit
• Opening that might let actor down
• Cellar entrance, sometimes
• Old football manager shown the exit? It's goes down very theatrically!