It's a billion-dollar ship superhighway of huge global importance. But this notorious and popular stretch of water is also home to some shocking secrets.
"All officers including the captain are dead, lying in chartroom and bridge. Possibly whole crew dead … I die."
This was supposedly the final chilling SOS message from on board the Dutch vessel the SS Ourang Medan, which mysteriously went missing in 1948 while sailing the Strait of Malacca during clear weather and calm seas.
When the crew from the nearby Silver Star ship answered the distress call and boarded the stricken vessel, they were reportedly greeted with a nightmare. The entire ship was littered with corpses — including a dog — with terrified expressions frozen on their faces.
Eyeballs bulged from their sockets, mouths were wide open as if in the midst of screams, and arms were outstretched as if they had been reaching for something. Oddly, the bodies showed no signs of any injuries.
The boat was to be towed into port but a fire broke out, leading to an explosion that sunk it.
However, there's a twist to this story: To this day nobody has found a shred of evidence the boat had even existed, and it has become one of the most controversial maritime legends in history.
Just what happened to the ship — if there really was one — remains a mystery. While some historians argue the incident never happened due to the fact there were no logs on the Silver Star detailing the rescue attempt, conspiracy theorists believe several countries worked together to cover it up.
Besides, why didn't the coast guard report what had happened until May 1954?
Others theorise noxious gas bubbled up from fissures in the seabed and engulfed the boat, while some even blamed the supernatural.
An eyebrow-raising "top secret" CIA document about the incident, which wasn't released to the public until 2013, pondered whether it may have involved "something from the unknown".
The letter was penned by C.H. Marck Jr, assistant to the Director of the CIA Allen Dulles, in 1959 and addressed to an unknown recipient.
"I feel sure that the SS Ourang Medan holds the answer to many of these aeroplane accidents and unsolved mysteries of the sea," he wrote.
Marck then made reference to "fiery spheres" of destruction before concluding: "The enchanting sea, what terrifying 'secret' does it hold? I feel sure that the SS Ourang Medan also holds the answer to this 'secret'."
Ultimately, there are many unanswered questions that remain about the ship, and it seems unlikely we will ever know what really happened.
'World's deadliest waters'
According to the Stanford Journal of International Relations, "The strait is one of the most important shipping lanes in the world, accounting for a third of the world's trade and half of its oil shipments … The strait is also one of the world's most dangerous maritime 'choke points' and a hotspot for transnational crime."
Piracy is the main crime of concern here. While piracy has been an issue in the Strait of Malacca for centuries, the 1997 Asian financial crisis and the end of the Suharto regime in Indonesia sparked further problems due to poverty.
Overfishing and pollution worsened the situation, pushing some local fishermen to undertake desperate acts such as hijacking crew and boats for ransom and kidnapping.
"Small-scale criminals — mainly impoverished Indonesian nationals — carry out the majority of these attacks, though the International Maritime Bureau believes that a handful of criminal syndicates based in Indonesia and Malaysia are responsible for the larger scale hijackings," the Stanford Journal states.
There are also concerns these groups of pirates may have connections with warlords or terrorist movements.
A dark picture of the region was also painted by a Time article from 2014 that called the Strait of Malacca the "most dangerous waters in the world". It detailed one piracy case where $2.6 million of fuel was stolen from a tanker called Orapin 4, which had left Singapore and was bound for Borneo.
Ten armed men climbed on board, locking the crew below deck and removing letters from the boat's stern so that it spelled "Rapi". Nobody could track the ship and the men were able to unload more than 3700 metric tonnes of fuel onto another boat.
It was the sixth attack of this nature within the space of just three months.
These figures would hardly surprise many locals, considering southern Asia was the location of 41 per cent of the world's pirate attacks between 1995-2013, leaving 136 dead. There were 43 violent events reported in the waters around Indonesia in 2017, including one hijacking.
Meanwhile, newly-released figures on piracy by the International Chamber of Commerce's (ICC) International Maritime Bureau show piracy and armed robbery increased on the world's seas in 2018, up to 201 incidents recorded compared with 180 in 2017. While patrols by Indonesia have reduced incidents in the Strait of Malacca to 36 during 2018, with just six crew being taken hostage and threatened, vigilance is still urged.
And in Malaysia, particularly off Sabah in the east, the rate of attacks is still a "concern" with five crew from two boats reported as kidnapped, along with shootings.
However, piracy is far from the only issue along the Strait of Malacca. From bloody battles to mysterious bodies turning up on nearby beaches and a desperate hunt for lost treasure, here are some other incidents that have occurred there over the years.
900 perish at sea
There's a horror history of bloodshed here. The Battle of the Malacca Strait during World War II was a naval battle that led to the sinking of the Japanese cruiser Haguro. More than 900 people perished.
The wreckage of the ship was surveyed in 2010, and by 2014 it was noted as having been destroyed by illegal salvagers.
Floating bodies wash ashore
Just last December, police were baffled by strange items floating in the waters off Bengkalis Island, Rau. It turned out they were parts of more than a dozen decomposing bodies that had washed up gradually since November, including the head of a woman.
"Based on our probe, we estimate that the bodies had been floating in the waters for more than a month," a Bhayangkara Police Hospital spokesperson told the local Antara news agency at the time.
No signs of violence were found on the bodies.
As they continued to probe the cause of the deaths, police discovered that some victims had been Indonesian workers on a ship that had crashed into a huge wave and sunk. However, some of the deaths are still a mystery.
Lost treasure worth billions
The strait also hides unbelievable riches in the form of sunken treasure. One example is the Portuguese vessel Flor de la Mar, which is still lost at the bottom of the sea, full of more than $3 billion worth of treasure. The ship hit a reef off the coast of Sumatra in 1511 during a storm, splitting in two and killing nearly all of the 400 people on board.
It had been full of bounty, including more than 60 tonnes of gold objects and 200 gem-filled chests with diamonds and rubies that had been stolen from the sultan's palace in Malacca.
The wreckage has never been found, despite many attempts.
Disappearance of MH370
The Strait of Malacca is also a piece of the puzzle of the greatest aviation mystery on the planet, the vanishing of Malaysia Airlines flight 370.
Defence radar last detected the plane turning back across Malaysia, heading northwest up the Strait of Malacca then disappearing out of range just north of Sumatra.
There has been renewed calls for a search of the area, after a group of fishermen spoke out last month claiming they had witnessed the plane descending as if to land in the notorious waterway. However, the plea has been denied by local authorities who say there's no evidence the wreckage could be resting in the waters there.