Possible Clues:

• Capital by the Hindu Kush
• Sailor beset by bad luck without a cent acquires capital
• City nightclub — a killer turns up to show
• Afghanistan's largest city
• Left tips for kitchenmaid and butler under lamp — or place high up
• Graduate goes back to university in Kuala Lumpur or in Afghanistan
• Afghani capital
• Site of a presidential palace called the Arg
• National Museum of Afghanistan city
• World capital located more than a mile above sea level