The film opens on Martín Santomé's 49th birthday, a widower and the father of three children: the eldest, the embittered Esteban ; the caring middle-child Blanca and Jaime, a closeted homosexual. He goes to work thinking they have forgotten his birthday, and once at the office, he assigns two new employees to their jobs: the effeminate, nervous Santini and the young Laura, with whom he soon develops a bond. Back home, Martín is surprised with a party thrown by his children. After having a one-night stand with a woman he met on the bus, Martín starts going through a series of events that alter his life completely. Santini has a nervous breakdown at work and rants against the complacency of his co-workers; he is subsequently replaced, though the breakdown marks Martín and forces him to look at his own life. His son Jaime finally comes out and decides to leave home to save the family from embarrassment and further complications. Topping it all, Martín, who has befriended Laura, professes his love for her at a café and implores her to look beyond the age difference and give him a chance. She accepts. The two start dating and Martín regains his wont of living. Their relationship never falters, and hints of infidelity are quickly dismissed. He moves into her apartment, forsaking his son and daughter. This upsets Esteban even more, who blames his father for giving him a mediocre life. Martín implores him that it is never late to change, and they reconcile. The film's climax begins with the untimely demise of Laura, who contracts flu and dies from heart failure shortly thereafter. Martín once again regains his bleak view of life and the world. He realizes that his romance with Laura was nothing but "a truce with life". The film ends on an ambiguous tone, as Esteban tries to comfort his father, roles inverted, and the camera centers on Martín, leaning against the wall, looking more hopeless than ever.
Argentine actor Sergio Renán had been performing in films since 1951 under the direction of noted filmmakers Mario Soffici, Lucas Demare and three times under Leopoldo Torre Nilsson. It was in his last collaboration with Torre Nilsson, in 1973, that he met fellow co-stars Héctor Alterio and Norma Aleandro. A year later he would cast them both in a starring role and a cameo appearance respectively in his film debut, La tregua. A year after its release, La tregua was submitted to the Academy Awards and won a nomination but lost out to Federico Fellini's Amarcord. The film has since gained cult status in Argentina. A Mexican remake was made in 2003.
