On the tragic night of February 28, 1986, Swedish Prime Minister Olaf Palme was assassinated on the streets of Stockholm. He was walking home with his wife after enjoying a film in the heart of the city when the shocking event took place.

In the aftermath, despite the presence of more than 25 witnesses, the investigation struggled to pinpoint the identity of the assailant. Eyewitness accounts varied significantly, leaving authorities with a fragmented picture of the suspect.

The police, eager to find leads, released a sketch based on witness descriptions. Unfortunately, it was later revealed that the sketch was drawn from the testimony of a person who hadn’t actually seen the perpetrator.

Amidst the chaos and confusion, numerous conspiracy theories emerged. One particularly intriguing theory suggested that Palme was targeted by a South African spy, allegedly due to his staunch opposition to the apartheid regime.

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Numerous conspiracy theories were posited, including that he was killed by a South African spy because of Palme's opposition to apartheid.

Other theories include that he was killed by Chilean fascists, the CIA, the police, Kurdish militants and the Yugoslavian secret service.

Three years later, habitual criminal Christer Pettersson was identified as the killer and tried and convicted.

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But it was revealed police had directed witnesses, including Palme's wife, as to who the suspect was in the line-ups.

Pettersson was freed a year later on appeal.

But an alleged eyewitness to the murder claimed his claims to the police had been repeatedly ignored.

Stig Engstrom spent years detailing how he arrived at the crime scene moments after the shooting and had pointed out the killer's escape route to police.

Engstrom repeatedly told his story to the media in the years following, his details becoming more vivid over time.

Police brushed him off as an attention seeker and a publicity-seeking nuisance.

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But in 2020, years after Engstrom's death, prosecutors named him as the likely culprit of Palme's murder.

The leading theory is Palme's murder was purely opportunistic.

Palme happened to be walking past as Engstrom left work at an insurance company.

Because he was dead, the investigation was closed after 34 years.

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