While the joint Scottish and FBI investigation closes in on the identity of the 'mystery shopper', a CIA asset could hold the key to the identity of the Pan Am 103 bombers.
Follow the investigation into the crash of Pan Am 103 from both sides of the Atlantic and discover the devastating effect it had on the small town and the families who lost loved ones.
The Bombing of Pan Am 103 - Series 1, Episode 5 Synopsis and Schedule