From the Back Cover:
The next golden bullet has your number on it!
BRIEFING: Francisco Scaramanga — the Man with the Golden Gun — is the world's consummate assassin. His fee: one million dollars. His signature: a golden bullet. His specialty: a single shot to kill his victim. Now Scaramanga is after a brilliant scientist and his Solex Agitator, and with it he will be able to create the ultimate firearm — a solar gun that uses the energy of the sun as its projectile. The master killer must be stopped before he can unleash his new golden gun against the free world.
MISSION: M.I.6 has assigned you to protect the Solex Agitator and to stop Scaramanga. The trail of the golden gun leads you to the mysterious Orient, where Scaramanga has gathered his powerful assistants to stop you at any cost. Even if you manage to find Scaramanga, you must confront him in the ultimate test of your skills inside his maze of death!