Possible Clues:

• Put in motion part four of drama at Globe finally
• Put into operation
• Trigger
• Prompt report of busy boat crew
• Turn on pretence that is about duty
• A vet working with cat, I start operating
• To start penultimate section of Macbeth, for example, was worrying
• Make usable, as a credit card
• Fourth part of play -- at end of scene set off
• Turn out unattractive for trip