Lily, hidden with her blind grandfather who does not suspect a thing, discovers another intruder there. Angèle. An elderly woman, naked, asleep on the living room sofa next to her grandfather. Suddenly Angèle wakes up, and face to face with Lily, immediately becomes invisible. To prevent Lily from divulging the secret of her invisibility, Angèle offers Lily to take her to her home where she can make her invisible as well.

Ayoub, in a relationship with Valérie, and Theo's dad (8 years old) has to deal with his wife's depression and her recent placement in a rehab center on a daily basis. But now he also has to face a sudden shameful situation: he becomes invisible. He immediately goes to the emergency room. To avoid sowing panic, Nathan, Laurence's husband and director of the Creux hospital, locks up Ayoub against his will in order to be able to manage him in the greatest secrecy.

After a night of detention, Ayoub manages to escape. He must absolutely come to an appointment with the social worker for the care of his son. But invisible, he risks triggering everyone's panic and losing custody of Theo. Theo must become his accomplice. But for that, he must reveal his invisibility to him ... without traumatizing him.

Other cases of invisibility arise. In an inaccessible part of the hospital, linked to Victor's past, Nathan organizes a quarantine. He also absolutely has to find Ayoub his patient zero, who could help him better understand the epidemic. Laurence, for her part, is convinced that the epidemic of invisibility is linked to the electromagnetic pollution of the new 5G antenna in Creux. She resumes her fight against the antenna.

Under the gaze of the police who don't see her, Angèle pushes Lily from the top of a bridge and makes people believe in suicide. The announcement of the suicide collapses Laurence and Nathan. Laurence understands that Nathan lied to her, and that he too knows that there are invisible ones. Their couple breaks up.

Threatened by Angèle, Laurence decides to take her father and Lily to the EHS camp, which is sheltered from the Antenna waves in a blank zone outside the city. Laurence reveals Lily's invisibility to EHSs and rallies with those who have long wanted to take action and destroy the antenna rather than negotiating with the authorities.

Nathan discovers Pierre and his vision which allows him to see the invisible ones. In exchange for finding Lily, Pierre helps Nathan and his team to collect in the houses the invisible ones they need for their tests. They put them to sleep with gas to take them by force to the hospital. Laurence discovers that Nathan has locked his daughter up with other invisible people. With no choice left, she launches the operation against the antenna.