Four lonely and disenfranchised urbanites in contemporary Mexico City: a preteen boy under tremendous emotional strain, the pretty cashier with whom he is infatuated, an enraged and embittered cabbie, and the estranged daughter of one of his fares. Per the film's title, these characters pair off, finding unexpected hope and salvation in one another.

Camila, after a couple of months of the loss of her parents, continues to mourn during the Day of the Dead, the colorful and festive traditions do not do justice to the loneliness and helplessness.

A man discovers he has been crying for two months without even realising it. His face has an impenetrable and serious expression. Strangely, his tears have decided to work in a reverse way, transforming the inside of his body into a waterfall. The water has started pooling at his feet.

Humberto works as a night watchman at a remote and desolate construction site. One night he becomes, unwittingly, the sole witness to a cover up. Afraid of being retaliated against lest he come forth, he decides to keep quiet. Gradually and without him being aware of it, Humberto ends up inflicting on his family the same violence from which he´s running away.

A shy and feeble architect is victim of a violent and abusing surrounding. The pressure builds up until he is pushed to the limit of his own humanity.