Walkthroughs
For legal reasons, the document that contains the walkthrooughs has to remain in its original form.  So I made a table to make it easier for you to navigate it.  If you have time, read through the whole FAQ, it's really great.
 
 
Agent Walkthroughs Special Agent Walkthroughs Perfect Agent Walkthroughs
 

AGENT Walkthroughs
 
Mission 1  Defection Investigation Extraction
Mission 2 Hostage One
Mission 3 Stealth Reconnaissance
Mission 4 Infiltration Rescue Escape
Mission 5 Espionage Anti terrorism Confrontation
Mission 6 Exploration Nullify Threat
Mission 7 Defense
Mission 8 Covert Assault
Mission 9 Battle Shrine
 

SPECIAL AGENT Walkthroughs
 
Mission 1  Defection Investigation Extraction
Mission 2 Hostage One
Mission 3 Stealth Reconnaissance
Mission 4 Infiltration Rescue Escape
Mission 5 Espionage Anti terrorism Confrontation
Mission 6 Exploration Nullify Threat
Mission 7 Defense
Mission 8 Covert Assault
Mission 9 Battle Shrine