Perfect Dark is GoldenEye's gameplay sequel.  Not the story sequel.  It involves more and more weapons than GoldenEye and a co-op campaign missions to help you if you get stuck.  This game also has dialogues which means not only do they have the subtitles, the characters actually speak.  GoldenEye doesn't.  Plus the sound effects of footsteps make things more realistic.  Very challenging and very fun.  Beat GoldenEye first, then get this game and beat it.