False Flag: Part 1 (S04E03)

Contemporary London: A garage is demolished. As the building falls apart, demolition work is halted at the sight of a skeleton sitting in the driver's seat. An unexploded bomb is found under the car which is soon linked to an Irish terrorist cell from the late 1970s. The team tread carefully to unravel the story of the would-be bomber. Why was he killed and why did the bomb fail to detonate? (iTunes)