Muted ending explained: What happened to Sergio?

Netflix Spanish-language thriller Muted (El silencio) follows Sergio Ciscar, a young man who has never spoken about why he murdered his parents in a violent rage when he was underage – even when he was found guilty and sentenced to six years at a psychiatric facility.

But on his release, psychiatrist Ana Dussel, who is monitoring his re-entry back into society, learns what really happened that fateful night – and why.

If you've finished watching Muted and are looking for a rundown of that devastating ending, read on.

Muted ending explained: what happened to Sergio?

Sergio was treated as a science experiment by his mother Blanca, who was a psychiatrist. He was "gifted but had problems with self control", so she decided to medicate him and monitor the effects over time. She claimed she was motivated by a desire to stabilise her son, but instead Blanca was driven by a morbid scientific curiosity.

Sergio's dad Javier, who ran clinical trials at the hospital, sourced the drugs by collaborating with several laboratories.

There was an observation room hidden behind a one-way mirror in Sergio's bedroom from which Blanca would watch her son and record his behaviour, keeping detailed written, audio and video files on him.

Ana also knew Blanca – the latter was her mentor and greatest influence – which is how she first came to be aware of Sergio. While he was locked up, she would write letters to him under a false name and over time, developed romantic feelings for him, which continued to intensify during her own study of Sergio; so much so that she chose him over her family in the final episode.

While the surveillance operation she was leading was designed to assess whether he remained a threat to society, Ana was more concerned with proving his innocence. By contrast, police inspector Cabrera, who was corrupt, believed Sergio was a "psychopath" and wanted him behind bars.

In the finale, we finally learned what happened that fateful night.

Initially, Sergio claimed that his dad had pushed Blanca off the balcony. In his version of events, his mother was planning to experiment on his sister Noa, who was later adopted by Ana and her husband. He demanded that she stop, but Blanca refused. Sergio alleged that his father then stepped in and ordered his wife to terminate her study, but again she refused and a colossal argument ensued.

Sergio claimed that his dad pushed his mother off the balcony before jumping after her, unable to live with the consequences of his actions – but Noa revealed that it was Sergio who had murdered his parents. He demanded that his mother stop drugging him, but she had no desire to draw her experiment to a close. Unable to cope with her abuse any longer, he was overcome with rage and attacked his mother with a knife, which caused her to fall off the balcony. A few moments later, he also pushed his father to his death.

With the truth now exposed and the police gathered outside his apartment, Sergio chose to end his life. After sharing a tender moment with Ana, he walked onto the balcony and left the world in the same way as his parents, leaving the psychiatrist alone with her grief.

If you have been affected by the issues raised in this article, help and support can be found by visiting Samaritans, and via the charity's 24/7 helpline on 116 123. Further help and guidance can also be found on the NHS website.

Muted is available to stream on Netflix now. Sign up for Netflix from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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