Possible Clues:

• A few hours to kill, e.g
• A ringer perhaps for big Ben has a few hours to kill (4,2,3'1,5)
• At this moment, Fingers' hangout is not busy (4,2,3'1,5)
• For some period, Fingers is not busy (4,2,3'1,5)
• Wristwatch supplies this opportunity for relaxation
• Left with this, as the enemy hasn't caught up?