A former Soviet secret agent, Valentina Michailova murdered the Press officer of the right-wing of the Freedom Romanian Party with a garrote. Since her motives are very personal, the ICC have to hurry to catch the professional killer . Her next victim is Solbak, the head of the Party. Marco takes a new step in the investigation of his missing sister.

The series taps into a fictional unit mandated by the International Criminal Court (ICC) to investigate cross-border crimes and ultimately bring global criminals to justice. Crossing Lines is set in the world's most exotic locales, where an elite team of eager cops work to solve the most notorious international crimes.