Unlock extra stuff:
     Beat  the  following  levels  under  the specified time to unlock
multiplayer levels and more skins:

Level:               Mode:         Time:      Unlock: 
Subway               Agent         2:15       Castle level 
Masquerade           Agent         3:15       Air Raid level 
Night Watch          00 Agent      2:20       Forest level 
Turncoat             Agent         3:20       Capture The Briefcase level 
Whole game           00 Agent      Any        Golden Gun level 
King's Ransom        Agent         2:20       Team King Of The Hill level 
Cold Reception       Secret Agent  3:15       Sky Rail level 
City Of Walkways     Secret Agent  3:45       Covert Skins 
Masquerade           00 Agent      4:20       Scientist skins 
City Of Walkways     Agent         3:35       Civilian skins 
Cold Reception       00 Agent      3:25       Exotic skins 
A Sinking Feeling    00 Agent      2:55       Navy skins 
Midnight Departure   Agent         3:05       Soldier skins 
King's Ransom        Secret Agent  3:45       Security skins 
Whole game           Agent         Any        Contemporary Skins 
Whole game           Secret Agent  Any        Classic skins 
Courier Secret       Agent         2:00       Suit skins 
City of Walkways 2   Agent         3:00       Wildfire mode 
Thames Chase         00 Agent      4:25       Exotic weapons mode 
Fallen Angel         Secret Agent  2:45       Gadget war mode