Case File

The Lluís Gros Case — Child Sexual Abuse in Catalonia

El Masnou, Barcelona, Spain — Convicted offender remained free for years

Published June 9, 2026

The Lluís Gros Case — Child Sexual Abuse in Catalonia
EVIDENCE

Quick Facts

Perpetrator(s)Lluís Gros Martí (also referred to as Lluís Gros Martín)
Victim(s)KrimiNyt has chosen not to publish the names of the victims
Crime sceneEl Masnou, Maresme, province of Barcelona, Catalonia, Spain
Date of crime2007–2011
Type of crimeSexual abuse of minors, corruption/prostitution of minors and other sexual offences

The Case

The Lluís Gros case is a Spanish child sexual abuse case that exposed serious failings in the judicial system's enforcement of criminal sentences. Lluís Gros Martín, a former cinema manager from El Masnou in the Barcelona province of Catalonia, was convicted of sexually abusing multiple minors and sentenced to 24 years in prison. Despite this lengthy sentence, Gros remained at liberty for years, a shocking fact that became the central focus of the 2024 documentary miniseries Hunting a Monster (Cómo cazar a un monstruo).

The case represents not only a horrific series of crimes against children but also a disturbing illustration of how convicted offenders can sometimes evade imprisonment even after judicial proceedings have concluded. The documentary investigation brought renewed attention to both the original crimes and the systemic failures that allowed a sentenced child abuser to walk free.

The Crime

Lluís Gros Martín operated as a cinema manager in the coastal town of El Masnou, a municipality in the Maresme comarca of Catalonia, located approximately 18 kilometers northeast of Barcelona. His position in the community provided him with both social standing and access to potential victims. According to the documentary description, Gros maintained a facade of respectability in his community while concealing a pattern of manipulation and sexual abuse that continued over multiple years.

Timeline

1 January 2007

Abuse begins in El Masnou

During 2007, Lluís Gros Martí begins contacting underage boys with offers of work connected to his cinemas in El Masnou.

31 December 2011

Offending period ends

The documented sexual abuse of minors at the cinemas takes place over the period 2007–2011, after which the offending period ends.

1 September 2019

Audiencia de Barcelona hands down verdict

In September 2019, Gros is sentenced by the Audiencia de Barcelona to 23 years and 8 months in prison and ordered to pay 46,500 euros in compensation to the victims.

5 November 2021

Tribunal Supremo upholds the verdict

Spain's Supreme Court rejects the appeal and, on 5 November 2021, upholds the sentence of 23 years and 8 months in prison in full.

19 May 2022

Gros arrested and jailed in Barcelona

On 19 May 2022, Lluís Gros Martí is arrested in Barcelona and imprisoned — months after the final ruling from the Tribunal Supremo.

1 September 2024

Documentary series 'Cómo cazar a un monstruo' released

In 2024, the documentary series based on journalist Carles Tamayo's investigation is released, renewing focus on the case and its course.

The cinema manager used his trusted position to identify and groom vulnerable minors. The exact details of his modus operandi, including how he selected victims and the specific locations where abuse occurred, have not been fully disclosed in publicly available sources. What is clear from court proceedings is that the abuse was systematic and involved multiple victims over an extended period.

The crimes involved sexual abuse of minors, with Gros exploiting his authority and community standing to maintain secrecy. The manipulation extended beyond the immediate acts of abuse, as Gros apparently created an environment where victims and their families felt unable to come forward or were not believed when they did.

The Victims

The identities of Gros's victims have been protected in accordance with Spanish privacy laws regarding minors who have suffered sexual abuse. What is confirmed through court records is that multiple children were victimized by Gros during his time as a cinema manager in El Masnou. The exact number of victims, their ages at the time of abuse, and the specific timeframe during which each was victimized have not been publicly disclosed in the available sources.

Spanish judicial practice typically protects the identities of child victims in sexual abuse cases, both during proceedings and in subsequent media coverage. This protection extends to details that might allow victims to be identified within their communities, particularly in smaller towns like El Masnou where such identification could be relatively easy.

The documentary Hunting a Monster examines the impact on victims and their families, though it respects the privacy protections that prevent full disclosure of victim identities and specific circumstances.

Investigation

The investigation that led to Gros's conviction involved Spanish law enforcement authorities examining allegations of child sexual abuse against the cinema manager. The specific police units involved, the timeline of the investigation, and the key evidence that secured the conviction have not been detailed in publicly available English-language sources.

What can be confirmed is that the investigation resulted in sufficient evidence to secure a criminal conviction in a Spanish court. The 24-year sentence indicates that the court found the crimes to be serious and involving either multiple victims, multiple incidents, or aggravating circumstances that justified such a lengthy term of imprisonment.

The investigation's findings were apparently solid enough to withstand judicial scrutiny and result in a definitive conviction. However, as the documentary later revealed, the conclusion of the trial did not mark the end of the case's troubling trajectory.

Trial and Verdict

Lluís Gros Martín was convicted of child sexual abuse and sentenced to 24 years in prison by a Spanish court. The specific court, the exact date of sentencing, and the precise legal charges under Spanish criminal law have not been identified in the available English-language sources.

Under Spanish law, child sexual abuse carries severe penalties, with sentences varying based on the age of victims, the nature of the abuse, and whether aggravating factors such as positions of authority or repeated offenses are present. A 24-year sentence represents a significant term of imprisonment, suggesting that the court found substantial aggravating circumstances in Gros's case.

The conviction should have marked the beginning of Gros's imprisonment and the end of his ability to harm additional victims. However, what transpired after sentencing became the most disturbing aspect of the case and the central focus of the subsequent documentary investigation.

The Scandal of Freedom

The most shocking aspect of the Lluís Gros case emerged after his conviction: despite being sentenced to 24 years in prison, Gros remained at liberty for years. This extraordinary situation raised fundamental questions about the Spanish judicial system's ability to enforce its own sentences and protect the public from convicted dangerous offenders.

The specific legal mechanisms or administrative failures that allowed a convicted child sex offender to avoid imprisonment are explored in the documentary Hunting a Monster, directed by Carles Tamayo. The series investigates the bureaucratic, legal, or procedural gaps that permitted this situation to continue.

For victims and their families, Gros's continued freedom represented a profound betrayal of justice. Not only had they endured the trauma of abuse and the difficult process of coming forward and testifying, but the judicial system failed to deliver the most basic component of justice: removing a dangerous offender from society.

Today

The Lluís Gros case gained renewed public attention with the September 6, 2024 release of the documentary miniseries [Hunting a Monster](https://en.wikipedia.org/wiki/Hunting_a_Monster) (Cómo cazar a un monstruo) on Amazon Prime Video. Directed by Carles Tamayo, the series investigates both the original crimes and the extraordinary fact that Gros remained free despite his conviction.

The documentary's impact was recognized with a Premio Ondas award, one of Spain's most prestigious honors for radio and television productions. The recognition highlighted both the quality of the investigative journalism and the public importance of exposing the failures that allowed a convicted child abuser to evade imprisonment.

The current status of Lluís Gros—whether he has finally been imprisoned, remains at liberty, or has died—is not specified in the available English-language sources. The documentary's investigation brought international attention to a case that exemplifies both the horror of child sexual abuse and the potential for judicial systems to fail victims even after successful prosecutions.

The case continues to raise important questions about sentence enforcement, victim protection, and the mechanisms needed to ensure that convicted offenders actually serve their court-ordered punishments. For the community of El Masnou and the broader public, the Lluís Gros case serves as a disturbing reminder that a conviction and sentence do not always guarantee justice or public safety.

Media coverage

TV series

  • Cómo cazar a un monstruo(2026)

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