After a wild party night for her 18th. Isabell Lauterbach's birthday finds her ex-boyfriend Ben Thiele dead. All memories of the night have been erased. Did she kill him? In addition to cocaine, raw nol, the so-called rape drug, is also found in Isabell's blood. Does the memory loss come from the K.-o. drops, or does it not want to burden itself? Marie Brand and Jürgen Simmel interview the party guests, including the sprint relay, in which both Isabell and Ben train have. Investigators focus on Isabell's best friend Ella Wittmer. Not only does it keep investigators from providing important information to protect themselves. Everyone involved seems to have a secret and a motive. Marie Brand and Jürgen Simmel try to reconstruct the crime night. When they get the crucial clue to the perpetrator, a race begins over time, since the murderer already has his next victim in his catch.