Possible Clues:

• Stage actors
• They perform weird shanties about power
• Stage set?
• They perform plays initially in ramshackle shanties
• Capable of making a scene, as she paints all over the place
• Capable of making a scene as she paints model
• Cast has inept point -- that's actors for you
• ... the odds are on McKellen's colleagues
• Performers of various shanties gathered round piano
• Actors