Andrea is confident that he has finally won over Agnese and, feeling romantic, he suggests that a wedding is organised in the ward for a patient in critical condition. Meanwhile, Gabriel makes an unexpected proposal that upsets the balance within the group of interns.

A patient sheds light on a secret about Lorenzo's private life that causes a stir throughout the ward. Meanwhile, Gabriel and Elisa must attempt to reconstruct the life of an elderly inpatient who appears not to remember anything about himself, but repeatedly utters a single word.

After finding the medical file on the patient who died because of a mistake, Andrea tries to reconstruct what happened before the shooting that wiped out his memory. Marco, who was responsible for this death, and Agnese are uncooperative. Alba and Riccardo struggle to rebuild their relationship and things also get complicated between Gabriel and Elisa.

A train accident turns the Internal Medicine ward into an improvised emergency room. All the doctors are required to do their best to deal with the emergency. One of the wounded is a girl who reopens an important chapter in Riccardo's past that the young man had considered closed forever.

The arrival of Elisa's older sister in the hospital, a likeable, charming actress, inexplicably makes the young trainee even more surly and bad-tempered. Andrea continues to delve into the years that amnesia has wiped out, while Agnese cannot mask her jealousy over the growing rapport between Giulia and Andrea.

Lorenzo has issues again with his ex-girlfriend Chiara, who is then hospitalized after overdosing. Marco and his wife feel increasingly threatened by the research that Andrea is carrying out on Satonal, the experimental drug that appears to have caused several deaths. Meanwhile, Gabriel has to explain to his community that he intends to settle in Italy.

Andrea finds himself in hot water when a former trainee accuses him of falsifying data from a pharmaceutical trial: unable to defend himself due to his amnesia, he seeks confirmation from people close to him. In the meantime, Lorenzo has to fight to get Chiara on the transplant list and Agnese has a sudden illness.

Agnese's condition rapidly deteriorates and Andrea receives the support of the whole ward in the attempt to discover what disease she is suffering from. However, the accusations levelled against him regarding his involvement in the falsification of data on pharmaceutical trials risk him having to leave the hospital for good.