From the back cover:
Now all the excitement and challenge of the James Bond movies and role-playing game are yours, without the need for a GM.
The game system for On Her Majesty's Secret Service goes beyond the traditional solitaire mechanic of just reading paragraphs and thrusts you into the middle of breakneck chases and deadly combats. Through the use of Action Cards and random NPC cards, the danger levels can change from moment to moment matching you character's growth from rookie to "00". As you progress, you gain Action Codes that can change the course of the adventure, bringing surprises and thrills you never thought possible with a solitaire game. On Her Majesty's Secret Service contains FOUR complete adventures that can be played individually or linked together, using James Bond or a character of your own creation.