Related Clues:

• Work that can't be done alone
• Abbott and Costello, e.g
• Tune two croon
• 2 to say 'Are you in debt?'
• Party gatecrashed by posh couple
• An act of duplicity?
• Associated pair in the clouds making a comeback
• Musical piece for two performers
• Trio less one
• Sonny and Cher, e.g
• 'I Got You Babe,' e.g
• The Dynamic ___
• Singing pair
• Song for Simon and Garfunkel, e.g
• 'It Takes Two' is one, appropriately