What can you do in free roam in L.A. Noire

There are a few things that free roam is most useful for:

• Locating 50 collectible golden film reels scattered over LA
• Locating secret locations where rare cars can be found and driven
• Completing random crime events and earning experience
• Completing the many achievements available
• Finding and marking the many landmarks of LA on your map
• Cause mayhem and chaos with no penalties
• Sightseeing

There are different levels of "free roam" in LA Noire. A new one is unlocked after completing each rank where the partner you had in that rank will be there, and a completely free roam when you complete the game.