Possible Clues:

• Tight-lipped
• Less than candid
• Skilled at dodging
• There's no limit to legitimacy of one who is guarded
• Wary when star of US gangster movies drops in at last
• Secretive, wary
• Secretive, a bit like a 20th-century avant-garde composer?
• Frank's opposite number gradually rising through banks in City
• Shrewdly guarded
• Arrangement of bars on Fourth of July - not open