At a Mexican military base, Captain Eduardo Barrón picks up not a rifle but a microphone. Swaying boot-to-boot, he belts out a song as the sounds of trumpets and accordions roar ...

Now, his successor has quietly begun to build an elite civilian investigative and special operations ... started his career.

Modern Warfare 2 barely continues the plot of the previous part – the main connection between them is only in the characters.