Possible Clues:

• Had some food on the way back - delayed because of puncture!
• Three consecutive notes let down
• Let down (balloon)
• Let the wind out of, braggart or balloon
• Let down, having been so in river
• Lower level in Scottish river
• Let out air
• Let down after US agent returned behind schedule
• Collapse of penthouse maybe owned by banker
• Collapse of French female no longer with us