i have all the deus ex games as well as most of the GTA games so any guys or gals have any suggestons?

If you put GTA as a complex storyline, I'm at a loss on what to recommend here.

Planescape: Torment.
One of most complex storylines in games ever.

You might try Neverwinter Nights if you are into RPG's quite liked the story. Don't know if it is the best one but you can try it.

EDIT: Forgot about Knights of the Old Republic. Thanks for bringing it up Jonni. That one I really enjoyed playing and reruning it again and again.

Or rather Mask of the Betrayer.
NWN 1's storyline is kind of... generic.

i tend to like the darker ones more

Don't forget part II (+ restoration mod). That's where the story really shines.

Alan Wake

Dark Souls and Demon Souls, No kidding.

Arcanum of Steamworks and Magick Obscura, it's pretty awesome.

Planescape Torment. And Planescape Torment. And Planescape Torment. And Planescape Torment. And Planescape Torment. And...

You get the idea. XD

Gemini Rue was kind of dark, and the story was great.

Of the top of my head - Sacrifice, Planescape: Torment, Gothic and Fallout.

Wait, you didn't finish, what was the last one on your list going to be??

If you have a (3)DS then 999 and Virtue's Last Reward. For PC: Resonance immediately springs to mind.

Um, and yeah, Planescape Torment too...