A supposedly simple break-in turns out to be a murder: the body of the owner Jian Chien lies in the development company Al Drones. Jörg Albrecht, the German managing director, suspects that sensitive data has been stolen from the company, since AI Drones specializes in the development and production of autonomous drone swarms. Thien Wong, the dead man's uncle, a high-ranking diplomat, who clearly rejects the obvious suspicion of Chinese industrial espionage, turns up at the scene of the crime. However, Ellen Lucas is not intimidated and continues to investigate in this direction. Claudia Bittner, the leading software developer at AI Drones, is suspected because the stolen data was on her computer. But she has a watertight alibi through her life partner Leon Kern.
Kern device, howeverthe focus of the investigation because Jian Chien bequeathed his entire fortune to Dissident's Freedom, a human rights organization for Chinese dissidents, for which Kern has recently started working. Kern's daughter from her marriage to a Chinese woman is being politically persecuted and has been held in China for years. What is the connection between Bittner and Kern about? What do the company Al Drones and the human rights organization have to do with each other? And did Jörg Albrecht really only want to produce drones for civilian purposes? Suddenly Thien Wong disappears. Ellen Lucas and her team scrutinize the distribution structure of Al Drones down to the last detail and penetrate deeper and deeper into the connection between the human rights organization and the politically persecuted. This is how they succeed in deciphering the Chinese riddle.

Regensburg is looking forward to the upcoming German Catholic Day. 100,000 visitors are expected. The anticipation is cut short when a monk's body is found. Finding place is the substructure of the stage, which is set up for the opening service. Inspector Lucas and her team immediately start investigating, because one thing is clear: the opening must not and should not be postponed. Her first lead leads her to the influential "Exercitus Sanctus Jesu" order, which is controversial among lay Catholics - mainly because of its opaque banking transactions. The monks of the order, under the leadership of the Superior General, are hiding something, it becomes immediately clear. While the investigators are researching on site, the situation worsens.
In an anonymous email, the cancellation of the opening service is requested, otherwise there will be a catastrophe. The connection between the dead man on the cathedral square and the blackmail is obvious. Ellen Lucas, who makes no secret of her rather church-critical attitude, gets into a fight with Boris Noethen.Because he is trying, not least out of religious conviction, to prevent a possible cancellation of the Kirchentag, which is in the spirit of Andreas Schneiderhahn, the organizer of the Kirchentag. Since the blackmailer's email also calls for the opening of all church property for refugees, a group of Catholics who are involved in church asylum come into focus. With the help of Tom Brauer, Ellen Lucas finds out that Martina Heise, a woman from this circle, definitely has a motive to take revenge.
But new suspicions also arise in relation to the "Exercitus Sanctus Jesu" order, and Brother Peter, a monk who was very close to the dead man, disappears. Then, in another anonymous email, no less is demanded than the distribution of the entire church property to the poor. An attached quote from the Gospel of Matthew is deciphered by Inspector Lucas and puts her on the right track. But it's about much more than a theological riddle, because the blackmailer is in possession of a large amount of explosives.