Goidsargi Estibaliz Carranza Zabala was born on September 6, 1978, in Mexico City. When she was five years old, her family moved to Spain, where she grew up in Barcelona. Carranza held both Spanish and Mexican citizenship. Her father, Armando Carranza Mendoza Lopez, was a well-known author who wrote about topics like esotericism and shamanism. He had previously worked as a journalist. Her mother, Angela Zabala, came from the Basque Country. Estibaliz also had a younger brother.

As a child, Carranza experienced a difficult relationship with her father. She later said in court that her family did not allow her to stand out or express herself. At the University of Barcelona, she studied economics at her father's insistence. During her early years, Carranza developed violent fantasies, particularly towards her father, whom she described as tyrannical.

She was engaged to her first fiancé for five years. However, she felt that he treated her as his possession. After she completed her studies, he ended the relationship because he was not interested in a serious commitment. Following this breakup, Carranza had thoughts of harming him, including considering tampering with his car.

Not long after, Carranza moved to Germany, where she first lived in Munich as an au pair. She had already learned German in childhood, which made her adjustment easier. After her au pair job, she worked at an ice cream shop in a village near Nuremberg, where she met her future husband, Holger Holz. Holz was fourteen years her senior and a member of the Hare Krishna movement. They married in 2002 and moved to Berlin.

Soon after their wedding, Holz began taking money from Carranza's earnings from her job as a waitress. He would later take her personal documents when she wanted to leave him. Holz's behavior became abusive, both verbally and physically. Despite this, Carranza stayed in the relationship and took another job in an ice cream shop, where she was also bullied and mistreated.

In 2005, the couple moved to Vienna and opened an ice cream shop called Schleckeria. Carranza was excited about having her own business, but Holz's controlling nature continued. During her time in Vienna, she met an ice cream machine salesman named Manfred Hinterberger. Two years later, she started a relationship with him and divorced Holz. However, Holz still lived in their apartment.

Estibaliz Carranza committed her first murder in 2008. She shot her husband, Holger Holz, three times in the back of the head while he was playing on the computer. After the murder, she left his body in their apartment for several days. She then bought a chainsaw and dismembered the body. Carranza encased the body parts in plastic bags and placed them in a freezer, which she later hid in the basement of her ice cream parlor.

In 2010, Carranza began a relationship with Manfred Hinterberger. This relationship soon turned sour, and Hinterberger’s frequent infidelity led Carranza to decide to kill him as well. She practiced at the shooting range to improve her aim. On November 21-22, 2010, after a night out together, she shot Hinterberger four times in the back of the head while he slept. Carranza then cut up his body with the same chainsaw she used for Holz. She stored the dismembered parts in the freezer just like she did with her first victim.

The disappearances of both men caught the attention of the authorities. On June 6, 2011, workers discovered the locked freezer while repairing a pipe in the basement. They found a handgun and several freezers filled with concrete. Body parts were identified as belonging to Hinterberger, and only a skull was found of Holz.

Following the discovery, Carranza tried to escape. She withdrew her money, took her passport, and attempted to flee to Paris. When she feared arrest at the airport, she traveled to Italy instead. Soon after, she was arrested in Udine. During questioning, Carranza confessed to both murders and detailed how she had disposed of the bodies. She was extradited to Austria, where her trial began in November 2012.

On November 22, 2012, Carranza was found guilty of double murder and sentenced to life in prison. Despite her actions, she gained significant media attention and published memoirs while serving her sentence. She remains a prominent figure in discussions of criminal cases in the German-speaking world.