A Somali teenager is found viciously bashed to death in a lonely railway tunnel. The investigation leads Koa and Malik to a Somali man, Asad, who is rumoured to be recruiting Somalis to return to Africa to fight for Al-Shabaab. The dead boy opposed Asad's teachings and his guardian, Samiira, is suspicious of this charismatic man. Worse, he holds great sway over her younger brother, Yusef. Despite Malik's efforts, it seems the violence Samiira fled in Africa has followed her, with tragic consequences. But has the war in Somalia had repercussions here in Australia, or is the killing a result of racial conflicts? Meanwhile, Internal Affairs investigate the shooting of Mahmoud, an accessory in the armed robbery, which causes conflict between Malik and Travis. Malik fears a vital link to the identity of the gang was extinguished with Mahmoud. He blames Travis. But is Malik's vision clouded by grief? Khalid, the dead bank robber, is found to have a wife, Sally Wilson, on active duty in Afghanistan. What has Afghanistan got to do with an armed robbery in Sydney? But the detectives' new leads end up in the morgue. The investigation is constantly thwarted by the strategies of a clever, ruthless gang. But who are they? Who is running the show?