A police officer is shot dead during an identity check at Hanover-Langenhagen Airport. What looks like a criminal's panicked reaction becomes increasingly mysterious. All surveillance cameras were out at the time of the crime. For Charlotte Lindholm, however, the case seems clear after just a few hours. To her own surprise, the suspected murderer is her childhood friend Manu. She is caught by Charlotte - a short time later, however, the Office for the Protection of the Constitution takes over the case in order to release Manu again. No solid evidence of their guilt was found. Charlotte is outraged and researches Manu's life. She finds out that Manu has worked for various aid organizations in Congo, among other places.
In her friend's secret file she finds evidence that she may have joined a radical group. This has set itself the goal of ending the brutal civil war in the Central African country that was tolerated by Western nations...