Summary

The Frontline documentary reveals David Coleman Headley's complex terrorist activities, including detailed surveillance and planning for potential attacks in Copenhagen and his critical role in the Mumbai terrorist siege in 2008. Headley, an American terrorist working with Al Qaeda and Ilyas Kashmiri, was eventually arrested by U.S. authorities after extensive monitoring and intelligence gathering. The story highlights the intricate nature of international terrorism, intelligence surveillance, and the strategic planning behind major terrorist attacks, ultimately showing how Headley was caught and became a witness for U.S. prosecutors.