Suspense? Pure suspense? Deep dark psychological suspense? I'm always pushing Patricia Highsmith..."This Sweet Sickness," "The Story Teller," and of course the first Ripley, "The Talented Mr. Ripley." Yes, she was inconsistent and occasionally off her rocker. But she was one of a kind. "Two Faces of January" wasn't bad either.
Barry Eisler's series has made the strongest impression on me of any recent offerings, but I would entirely understand if others disagree. I usually avoid "best sellers", figuring I can always catch up on them later, but tried HARD RAIN (2nd in the series?) on a whim. Was caught up in it instantly, and really enjoyed the ride. Especially the Japanese setting and culture-clash elements. The protag is not a pure, white knight good guy. He has earned his reputation, and the fact that he is caught between two worlds, and is in a position to not ever fully trust his employer(s) add to the conflict.