South Africa is a country of commissions, inquests, and inquiries. It has also left a remarkable number of files open. The five cases below span more than a century, from a ship lost in 1909 to an airliner lost in 1987. They have little in common except this: each has been investigated, argued over, and written about for decades, and each still has no final answer.

We start with the one that has haunted South African politics for almost half a century.

1. Robert and Jeanne-Cora Smit: Springs, 1977

Eight days before a general election, someone walked into a rented house in Selcourt, Springs, and executed one of the National Party’s most promising politicians and his wife. Nearly 49 years later, the mystery is still unsolved.

Robert van Schalkwyk Smit was 44 and on his way up. A Rhodes Scholar with a Stellenbosch doctorate in economics, he became Deputy Secretary of Finance at 34 and then served as South Africa's representative at the International Monetary Fund (IMF) in Washington from 1971 to 1975. In 1977 he was the Nationalist candidate for Springs, with the election set for 30 November. Party insiders spoke of him as a future Minister of Finance.

On the evening of 22 November, Jeanne-Cora phoned her husband’s office to say visitors had arrived at the house. It appears to be the last thing she did. She was shot with a .32 calibre weapon and stabbed 14 times. Robert, arriving home later, was shot with a .38 in the neck, head, back and chest, and stabbed once. Their driver, Daniel Tshabalala, found the bodies the next morning.

The killers left a signature. Sprayed in red paint on the fridge and kitchen walls were the words "RAU TEM". Robert’s briefcase was missing. The scene was handled badly, bloody shoe prints were never matched, and the investigation went nowhere.

Smit reportedly told people he held “explosive” information. The most persistent account is that, during his IMF years, he had stumbled onto secret overseas bank accounts and a foreign currency racket linked to the state, and meant to expose it. When the Information Scandal broke in 1978, revealing a secret government slush fund for propaganda, many assumed the two were connected.

In 1997 Beeld named former security policeman Roy Allen as the chief suspect. He denied it: “I am no murderer.” In 2006 the paper reported intelligence sources naming three men from the Bureau of State Security (BOSS): Allen, Dries Verwey, and Phil Freeman. By then Verwey had died (1980), Freeman had killed himself (1990), and Allen was living in Australia. No one was arrested.

The Truth and Reconciliation Commission (TRC) accepted that the killings were politically motivated and pointed to members of the security forces. Pik Botha, a former foreign minister, called it “one of the most haunting criminal mysteries in our country”. It remains so. What did Smit know, who ordered the killing, and where did the briefcase go? Those questions have outlived almost everyone who could answer them.

2. Rick Turner: Durban, 1978

Seven weeks after the Smits died, another killer fired through a window in Durban. Richard Turner (known as Rick), a 36-year-old philosopher at the University of Natal, was shot at his home in Dalton Avenue in Bellair, Durban, on the night of 8 January 1978. He died in the arms of his 13-year-old daughter, Jann.

Turner was a dangerous man by the standards of the time, though he never touched a weapon. His 1972 book The Eye of the Needle argued for a participatory, non-racial democracy, and he was close to Steve Biko and the reviving black trade union movement. In 1973 the state banned him for five years, confining him to Durban and barring him from teaching or publishing. The ban had only weeks left to run when he was killed.

The police found nothing. It is widely believed the security police were responsible, but no one has ever been identified. In later testimony, a former Security Branch officer said he had been watching Turner for two weeks when the surveillance was suddenly called off. Turner was killed the next day. “I felt that I was party to the murder of Dr Rick Turner,” he said.

In 2023 the National Prosecuting Authority confirmed it was investigating the case again, 45 years on. “Having all our questions answered will help,” Jann Turner said. The file is still open.

3. The Helderberg: SAA Flight 295, 1987

In the early hours of 28 November 1987, a South African Airways Boeing 747, called the Helderberg, reported smoke on board, then fell silent and plunged into the Indian Ocean east of Mauritius. All 159 people on board died.

The flight, from Taipei to Johannesburg via Mauritius, carried passengers in front and cargo pallets behind them on the same main deck. Judge Cecil Margo’s board of inquiry found that a fire in the cargo area brought the aircraft down. It could not say what started it.

That gap has been filled by theories ever since. The most enduring is that the government of the day, under arms sanctions, was quietly moving dangerous military cargo on civilian flights, with ammonium perchlorate, a rocket fuel oxidiser, the substance most often named. The TRC looked again in 1998 and concluded nothing in the cargo manifest explained the fire, while noting the case “raised significant questions” about the incident and the investigations that followed.

What burned on the Helderberg, and who put it there, remains unknown.

4. The SS Waratah, 1909

One of South Africa’s greatest mysteries is a ship. On 26 July 1909 the Waratah, a new Blue Anchor liner on her second voyage, left Durban for Cape Town with 211 people on board, having sailed to Durban from Sydney in Australia. She never arrived, and not a single body, lifeboat, or confirmed piece of wreckage has ever been found.

One passenger had a bad feeling. Claude Sawyer, convinced the ship was unsafe, got off at Durban and cabled his wife: “Thought Waratah top-heavy, landed Durban.” The next morning the steamer Clan MacIntyre exchanged lamp signals with the Waratah off the Eastern Cape coast and watched her pull ahead over the horizon. That was the last confirmed sighting.

Searches covered thousands of nautical miles. Over two decades from the 1980s, researcher Emlyn Brown hunted the Wild Coast for her, and one promising wreck turned out to be something else entirely. He eventually gave up: “I now have no idea where to look.” The likeliest answer is that a top-heavy ship met a freak wave on one of the world's most dangerous stretches of sea. The Waratah is still out there somewhere.

5. The Kruger Millions

Not every South African mystery is a crime. Some are treasure hunts. In 1900, as British forces closed on Pretoria during the Anglo-Boer War, gold from the Transvaal Republic’s reserves and the mint was moved east along the railway towards the Mozambican border. President Paul Kruger left for Europe that year. How much of the gold went with the state, how much was spent on the war, and how much was simply hidden has never been established.

The legend that grew from that gap says a fortune in gold bars and newly struck coins was buried somewhere in the Lowveld. Treasure hunters have dug across Mpumalanga and Limpopo for more than a century. Nobody has discovered the hoard, and historians have never agreed that it existed. It remains one of South Africa’s most enduring mysteries.