When Pablo Sandoval explains the "passions" of the main characters, in the pub scene, he compares Irene with Susanita in her bride-to-be mania. Susanita is a character in the famous Argentinian comic-strip Mafalda, by Quino. Susanita is a blonde elementary school girl who is known for always talking about her future handsome husband and her future beautiful wedding, when she is not gossiping about the neighbor's marriages.
The trivia items below may give away important plot points.
When Benjamín Esposito and Irene Menéndez Hastings go to confront the evil governmental officer who has released the assassin, the officer boasts about his powers and the differences between Benjamín and Irene recalling their last names: Irene is a Hastings (her cousins are "feudal lords" in the remote province of Jujuy) and Benjamín is a Esposito. Esposito in Italian means "orphan". In Spanish the word "expósito", which has almost the same sound as Esposito, also means "orphan", so the comment on the name is a complex transcultural and ethnic dismissing.
The soccer team seen scoring a goal in the stadium scene is called Racing Club. Guillermo Francella, who plays Pablo Sandoval in the movie, is a huge fan of theirs. Director Juan José Campanella is also a fan of Racing. Eduardo Sacheri, one of the writers and author of the novel on which this movie is based, prefers their rivals, Independiente.