NMPD HQ (level)

NMPD HQ is a Halo 3: ODST level. The characters, objectives and enemies are currently unknown, the only known thing is the NMPD HQ achievement, which is unlocked after you complete the level on normal or above and therefore unlock the Romeo character in firefight mode. There is also an achievement named Dome Inspector, which requires you to score 10 direct headshots on this level in order to be unlocked. This suggests that this is a large, wide level.