According to the little-known Osmosis Theory of Writing, while trying to write a tight, sharp, crime thriller, you should watch a tight, sharp crime thriller, like, say, Ronin (directed by John Frankenheimer, screenplay by David Mamet on JD Zeik's story). It helps if it's got insane chase scenes over roads you used to travel regularly (Paris, Nice, La Turbie). If you do this, the doors will fly open, and your screenwriting muse will spray you with inspiration, like so much shrapnel in a waterfront ambush.
That's the theory, anyway.
Your screenwriting kit should include: Ronin (with the Frankenheimer's commentary) and his 1962 classic, The Manchurian Candidate, on DVD, and Frankenheimer interviews at The Onion AV Club and Movie Express.