The mutiny that followed Elias’ death outraged the principal, who now imposes a firmer discipline than before at the centre. In addition, after Rita's death, no one doubts that a serial killer, an alleged imitator of the Crow's Nest, is responsible for the crimes. However, Amaia, Paul, Paz, Eric and Julio are not going to sit idly by. Not now that, thanks to Adèle, they believe that they can find Manuel alive. Will they arrive in time to save him? Who is behind the laboratory that is conducting those experiments with humans? and, above all, which is the purpose of all those experiments? On her side, Inés will discover something shocking about the past of León and hers. The young woman will be able to recompose some of the pieces that don’t fit with the story she’s been told, which will open many more questions about her past life. Who is she? What is the bond between she and León? And what is the connection between them and Darío Mendoza?