The Swedish counter-espionage has acquired a new secret weapon. The weapon is named Carl Gustaf Gilbert Hamilton, former clarteist and FNL member , lieutenant in the Navy's reserve and secretly trained as a field operator in the USA where he trained for Navy SEAL while studying political science and computer technology. During his Swedish conscription training as an attack diver, Hamilton was recruited by the former IB-the boss DG, who will be his personal mentor. DG has a vision to build a new generation in the intelligence service, consisting of competent field operators with the western world's best knowledge in both computer technology and small arms and melee, and Hamilton will be the first prototype.

After his return, however, Hamilton has not been able to get a job at the new military intelligence service, due to political complications and Swedish trade union rules and not least opposition from the military leadership who are skeptical of both the DG's vision and Hamilton's past as an outspoken communist. Instead, Hamilton has for the past two years worked as a computer specialist at the Security Police .

When a high-ranking Säpo official is found shot in his car at Djurgården, Hamilton is called in to take part in the murder investigation, and ends up under the head of Agency B, which works with the hunt for spies and terrorists. The murdered Axel Folkesson was a specialist in the Middle East and had worked alone with something called "Plan Dalet", which the murder investigators believe is an Arab terrorist act against Sweden. The suspicions are immediately directed at Palestinian terrorist groups and various Swedes with left-wing sympathies. During the course of the story, Hamilton feels more and more contempt and disgust for the Säpo chief, Henrik P Näslund, as Näslund's prejudices lead the investigation in the wrong direction, which only results in innocent left-wing sympathizers being arrested and harassed.

When Hamilton begins to make his first mark in the spy world, he is given the international code name Coq Rouge . This ironic code name arises during a meeting between Näslund and an Israeli colonel and is partly due to the fact that the Israeli intelligence service has long had the nickname "rooster chickens" for its Swedish colleagues and because Hamilton is an old communist, and for drinking a red wine with a red rooster symbol on the label.

The investigation takes Hamilton to Lebanon and Israel and back to Stockholm again. In Lebanon, he receives help from the PLO , through contacts from Ponti, and meets for the first time the young female intelligence officer Mouna. In Israel, he gets help from Shulamit Hanegbi, a young security officer, with whom he begins a short love affair.

Back in Stockholm, it all gets a brutal and bloody final when Plan Dalet is finally implemented. The terrorists who murdered Folkesson are not Palestinians at all, but the exact opposite, namely a group of Israeli field operators who came to Stockholm to carry out a massacre in the PLO's representation villa. Hamilton arrives late, when the terrorist attack has already begun and a large number of innocents have been murdered, but he manages to kill all four Israeli commandos. However, his boss Näslund lets the evening newspapers tell the public that it was Arab terrorists who were behind the attack, and seals the entire investigation.

For his efforts, Hamilton is awarded Gustav III's Medal of Bravery as the first Swedish officer in 80 years. He is also rewarded by DG getting him admitted to a captain's course at the Swedish National Defense College, so that he can get a break from the Security Police and become easier to instead employ in the military.