Last year Samir Madani, co-founder of TankerTrackers.com, noticed a mysterious ship off the coast of Lavan Island near Iran, appearing to take on cargo from another ship. It had turned off its transponder, making it harder to track. However, Madani, who runs an independent online service that tracks and reports shipments and storage of crude oil, found the ship through satellite photos on December 6, 2019. The same ship once again pulled a disappearing act, although this time at least 28 crew disappeared with it for ten days, only for the ship to show up off the coast of Iran and for the crew to appear back in India simultaneously.The ship in question is called "Gulf Sky" and it has been at the center of an international quest by the US government to stop Iran’s Islamic Revolutionary Guard Corps from laundering money and breaking sanctions by using front companies to acquire ships and smuggle weapons, oil and other cargo. The story is so complex and convoluted that it spans continents, involves human rights groups that sought to help the crew stranded on the ship, and now involves an alleged “hijacking” that took the ship from detention off the coast of the United Arab Emirates to an anchorage several kilometers off Iran’s Bandar Abbas.To understand how we got here I spoke at length with Madani who helped piece together missing details of this tanker’s movements. Last year, the Gulf Sky was named the MT Nautic and had recently been sold. The beneficiary owner was supposed to be a company in Oman. It had a crew of 28 and a captain from India who was ostensibly operating it for a company in India. We know this from details later released by the human rights group that was involved.According to Madani’s data, which he acquired through examining the ships transponder history of travel. Prior to its first disappearance, the ship was doing normal business, picking up oil from Saudi Arabia and the UAE and going to India and Oman. It was in Mumbai and New Mangalore in July and August 2019.Then in November, the ship made its way from off the coast of Fujairah - an Emirate of the UAE - in the Gulf of Oman, passing the port of Khor Fakkan, towards the Straits of Hormuz. This was a tense time for the US and Iran, as well as tensions being high in the Gulf. In the Spring of 2019, ships had been damaged by mines near where the Nautic had been anchored - they themselves had also been attacked in June 2019. Later a British ship named the "Stena Impero" had been seized by Iran. It only left Iran’s waters on September 27, 2019. Around this time the Nautic had changed ownership, although reports indicate that its mysterious owners in Oman had sought to acquire it since May 2019, when US-Iran tensions began to escalate.On November 30, the ship said it was going to Basra, according to logs analyzed by Madani. It sailed hundreds of kilometers into the Persian Gulf but never made it to Basra. Instead it switched off its automatic identification system transponder and disappeared on December 2. For five days it was gone. Madani found it near the island of Lavan, one of several places that tankers take on illicit cargo from Iran. This ship-to-ship transfer is a way of doing business without needing to go to port. The ship was seen on satellite with a very large crude carrier or VLCC giant ship from Iran’s National Iranian Tanker Company. The Nautic has a distinct shape. It’s a Suezmax size ship, 274 meters long and 48 meters wide and red on top. It stands out, says Madani. And it stood out in December for what looked like an attempt to evade detection.The ship left Lavan Island and sailed back through the Straits of Hormuz to an anchorage off the UAE on January 14, and then at a single-point mooring off Oman’s Sohar port on January 18. It sat around for a week and left on January 25. It’s not known what the tanker was carrying at the time. It could be oil or gas condensate. Madani says it is important to be careful in determining what was on board.The vessel also appeared to be purposely attempting to appear like it hadn’t taken on cargo, claiming its draft was only 8.5 meters below water. The Gulf Sky then returned to anchor off the UAE where it remained for six months, then one day disappearing in to thin air. It wasn’t until mid-July that a journalist reached out to Madani to ask if he could help find the ship. It had a distinctive deck so he remembered it and was able to look using satellite images to find it off Iran. With its transponder off, he compared it to other known vessels that have their transponders on. After disappearing from the UAE anchorage, there it was, off Hormuz Island, several hundred kilometers from its last known location on July 5, where it had been for months.Not much is known about the days aboard ship between January and May 2020, except that we know the COVID-19 crisis began, the UAE shut down airports and many things were grounded to a standstill. The US was also involved in increasing tensions with Iran. Rocket attacks on US forces in Iraq in December led to US airstrikes and protests at the US embassy in Baghdad. The US then killed IRGC Quds Force commander Qasem Soleimani.In May, the US government revealed an investigation into two men, Amir Dianat and Kamran Ali Lajmiri, Iranians allegedly involved in working with the IRGC Quds Force and channeling funds through the US to buy a tanker. This was a conspiracy involving the IRGC, which the US had designated a terrorist group in 2019. The US said it had disrupted the purchase of the tanker. The Washington Post noted that at the center of the case was the Gulf Sky, previously the Nautic. The US government sought civil forfeiture of $12 million involved in the purchase. The US noted that Dianat is also known as Ameer Abdulazeez Jaafar Almthaje and that he was linked to a company called Taif Mining LLC, who were “allegedly buying the tanker.”The US is involved in a long and complex struggle to stop Iran’s oil shipments and it has gone after tankers and their captains and owners in the past. The US had sought to stop the Grace 1 carrying oil to Syria in the summer of 2019, leading to Iran grabbing the British tanker in retaliation.The world of oil shipments and tankers is a murky one. Tankers may be owned by one company, run by another, operated by a third, crewed by a fourth and under the flag of a fifth country. Shell companies, operators, beneficiaries, re-flagging and naming of ships makes some tracking complex - determining who owns what and who is supposed to be paid. Crews of these ships sometimes don’t know who they work for, engaging in sanctions-busting activity they never signed on for. According to the Post report, when the US went after the money involved in the purchase of the Gulf Sky this set in motion a UAE decision to “seize the ship pending a hearing.” The UAE court acted on behalf of Nautic’s sellers. A US bank froze funds transferred back in October 2019, for a transaction involving the tanker. “An attorney for the ship’s seller, Polembros Shipping Ltd. Of Greece, said the firm has been cooperating fully with US prosecutors since learning funds from the brokered sale had been frozen.” The Wall Street Journal discovered that money that had been attempted to be transferred via Wells Fargo, intended for Crystal Holdings, a subsidiary of Polembros. The US alleged that to purchase Nautic the Iranians had gone to great lengths, involving a “Japanese agent” who did not know about the ties to Iran. The report said the tanker, after being purchased in October 2019, had gone to Kharg Island and was loaded with Iranian crude oil from the National Iranian Oil Company. That is apparently a reference to the Lavan Island trip on December 6. Kharg Island is hundreds of kilometers from Lavan, but the two are where Iranian tankers lurk to bring oil to other vessels through illicit shipments normally made with transponders turned off. Think of this coastline like a vast network of ghost ships as Iran tries to hide its activity.As of late, the vessel has been flying the flag of the Dominica, an island in the Caribbean. According to The National in the UAE the vessel only changed its name after it was acquired by Taif Mining in January 2020. It had apparently been flying a Liberian flag prior to the change. Taif Mining itself was only created in September 2019, these reports say, with the US alleging it was a front company.Now begins the long miserable tale of the crew and the mystery of what happened on July 5. Human Rights at Sea (HRAS) was contacted by the master of the vessel Gulf Sky, Captain Joginder Singh in mid-May 2020 to ask for help. They were told that the crew was stranded on the ship due to the legal dispute, and their financial troubles were adding up with living conditions deteriorating. There were 28 crew, of whom 20 Indian nationals submitted complains under the Maritime Labour Convention of 2006, HRAS notes in its May report. Most of the crew had come aboard in October 2019 or after.The crew faced many difficulties. Some had paid fees for the privilege to be trainees aboard ships like this and they were now stuck without pay and with family debts mounting. The HRAS report says that the ship had been “arrested” on January 27, 2020, due to the financial dispute between the previous owner who had not been paid. So it was sitting off the coast of Khor Fakkan. The report notes that while Taif Mining, based in Muscat, was the owner, the vessel was under insurance provided by Maritime Mutual Association Limited and the management of the ship was done by Maritime Ventures Private Limited. The crew complained that they were on water rations and salaries were paid rarely. The crew also appealed to Seven Seas Navigation in India, which was the “manning agency” they had worked with. Times of India says that United Island Maritime Ventures is an Indian company registered in March 2016 and that its directors Mohammed Afsar Mohammed Aziz and Shakeel Ahmed Shaikh are also directors of Seven Seas Navigation.HRAS helped raise awareness of the crew’s predicament and in June more press covered their situation. HRAS said it would work with the Dominica Maritime Administration in the Dominica to help put pressure on the owners and managers. Dominica Maritime said that they would use every legislative effort to make sure the mariners were repatriated.Between late June and early July something changed on the ship. Mediation on June 2 and further attempts on June 22 to help the crew were grinding along. Instead of a repatriation and legal cases playing themselves out or regulatory moves being made, the ship suddenly disappeared and ten days later the crew reported being hijacked. Some 26 of the crew were home in India by July 15. HRAS CEO David Hammond said he had taken a witness statement, according to reports.How did the vessel suddenly disappear on July 5 off the coast of the UAE, supposedly under “arrest” and re-appear in Iranian waters? There are many cases where the crew of ships like this go without pay or find themselves in these kinds of predicaments. One captain lived alone on a ship after the crew left because they hadn't been paid for more than 14 months. He was one of 220 Indian sailors brought home in 2017 due to these kinds of disputes. None of them disappeared or ended up in Iran and then back in India.What this tells us is that there is a well-known mechanism for dealing with cases where Indian nationals who are mariners are stuck on a ship and not being paid. The COVID-19 crisis may have made things more difficult. When the vessel disappeared on July 5 no one seemed to notice. Times of India only reported the crew “missing” on July 15, by which time they were on the way home to India. When the vessel disappeared it was under a Prohibition to Sail notice from the Commonwealth of Dominica and was under arrest by the UAE under an admiralty law injunction. Despite the injunction, Captain Singh only informed HRAS on July 15 that the vessel had been hijacked on July 5 and that now he and the crew were safe.The only indication that something concerning had happened was in a tweet on July 13 by Abhinav Singhal, a man claiming to be nephew to Chief Officer Suneet Kumar on the ship. He said he lost contact with him. He confirmed the crew was in India on July 15, days after expressing concern.Madani has attempted to reconstruct what happened. He posted online at TankerTrackers.com the location of the ship on July 15 and how it had moved since July 5 from the coast of the UAE to the coast of Iran. Using satellite photos from Planet Labs the ship can be seen off the UAE prior to July 5 and then it appears near Hormuz island on July 7. It then remains there through July 15. Its transponder is off the whole time, as if it is trying to hide. The transponder was turned off in the evening of July 5. Hours before the decision was made to turn it off a Seamax Swift ship from Khor Fakkan in the UAE visited the Gulf Sky, according to Madani’s data. The UAE-flagged off-shore supply ship made the journey and stayed for only 58 minutes before leaving. This raises questions about what happened on July 5 that caused the ship to suddenly leave and travel to Iranian waters. Why were two crew left in Iran when the others made it home? Was it only visa issues? How did the crew get home? Why didn’t authorities seek to stop the vessel from leaving? Many questions are left unanswered in the case of a vessel that is linked to numerous countries and various cases.Madani says he likes the part of his work when he can help people, as when he helped find the location of this vessel and the crew ended up safe. “It’s like cracking codes,” he says. There is a hide-and-seek game playing itself out today as countries under sanctions, such as Iran, seek to hide the cargo being put onto tankers. Using satellite images and transponders, as well as other methods - those like Madani are helping identify the real amount of oil being exported. This can involve tens of millions of barrels being illicitly moved around the world. US sanctions are taking a bite though. Dozens of vessels now avoid places like Venezuela, with captains fearful of being sanctioned -and innocent crew, who may not even know the destination of their tanker, end up in the middle, as in the case of the Gulf Sky.