Debailly is prisoner of IS in Iraq. DGSE asks Nadia to negotiate his release through an intermediary Shahanah, a corrupt art dealer, and promises her an EU Deputy Commissioner position in return for her help. Sisteron is sent to Iraq to meet Kurdish fighters and rescue him, but their attempt to do so during a sandstorm fails. He finds an SNCF railway points diagram left behind by IS, which DGSE believes is an attempt by 'Cochise', someone senior within IS, to communicate with them. Meanwhile Marina is working as a seismologist and is still traumatised by her experiences in Iran.