Possible Clues:

• Mr Cruise takes a cruise, first on one river then another
• River of Washington DC
• Quantico's river
• River under the Arlington Memorial Bridge
• Watergate river
• River in Washington
• River given to another, backing onto a third?
• Sink old coat in river
• Retired rozzer confiscates weapon, hawk having gone for US banker
• One river or another going South in direction of another going North