Some time ago, Ángel was starting a family, but the mistakes he made in the past continue to haunt him. Now, four hours have passed since the earthquake. Rescue operations at the hospital are ongoing with the help of students. Efforts to rescue survivors in Tlatelolco continue. Deep within the rubble, someone is calling for help.

One year earlier, Alberto triggers a conflict with the construction company he works for, claiming that the infrastructure of his building is in poor condition. By 1985, seven hours have passed since the earthquake. Beneath the rubble, Hilda and Toña are faced with a life-or-death operation. Camila arrives at the airport, with Ignacio and Guillermo hot on her heels.

Months earlier, Lucía and Pablo fall in love during a band rehearsal, with Lucía providing Pablo refuge from his home problems. Now, eight hours after the earthquake, they remain trapped under the rubble, running out of oxygen. At the General Hospital, a miracle amidst the tragedy occurs. Meanwhile, Camila, deprived of her freedom, may receive help from an unexpected source.