An unnamed body is found on a lake shore. The Stuttgart detectives Lannert and Bootz try to clarify the identity of the woman and find out that it was a Ukrainian living illegally in Germany. As they piece together the life of Taya Dawischko, the inspectors gain insight into the everyday life of people who live illegally in Germany and therefore try to remain invisible. As Lannert supportreceived from a friend of Taya's, who is also illegal, he promises not to betray the woman to his colleagues at the immigration office - a promise that rather strains Bootz's patience. On the other hand, in this way the two get on the trail of the employers and supporters of the murdered people - and Taya's two children, who are hiding out of fear and may also be in mortal danger...