The time is ripe for an investigator like Lisa Mattei. Lisa Mattei, the lead investigator of the Swedish Security Police, in her early 40s and married to a man several years younger, intends to celebrate her little daughter's birthday on her first day off in months when she receives an emergency call. Shortly after, the highest alert level is declared in the country, and a colleague from the British intelligence service MI6 contacts her: In 26 days, a member of an Islamist terrorist militia plans to blow himself up - along with the Swedish government. The Security Police must act. Is the first suspect, a charismatic young man with numerous female contacts, already the one they are looking for? Or is there a leak in Mattei's department?.