Brothers in Arms: Earned in Blood.
Call of Duty was fun when it was new, but the problem is, if you played one you've played them all. They're set pieces. Enemies spawn in a consistent, predictable manner, action is always triggered and scripted, and it's "Whizz-Bang-Wow!" the first few times you see it, but the gameplay is wholly unsatisfying as it's more like being on a set of a hollywood war movie than feeling like a real fight.
(I say this as someone who LOVED the first game and enjoyed the second, but grew tired of their formula quickly)