A mysterious plane crash in the Scottish highlands and a woman pursued by a hitman are cases investigated by the Anti-Terrorism Squad.

Gabrielle de Faujas, formerly member of a terrorist cell, flees from Paris after an attempt on her life en route to Canada, but the plane crashlands at Scotland. Fearing that Gabrielle may betray it to the authorities, the cell sends the hitman Constant Delangre after her. Will Delangre find Gabrielle before the local police can defend her?