It still isn't clear exactly what happened to the Russian-crewed freighter Arctic Sea, which mysteriously disappeared in European waters last month. Inconsistencies and the implausibility of the official story — it was a hijacking — have prompted considerable speculation.

Those imaginings have been spurred by the visit to Russia of Israeli President Shimon Peres and the "disappearance" for one day of Israeli Prime Minister Benjamin Netanyahu, who reportedly secretly visited Russia to discuss Iran. This incident sheds little light on Russia's relations with the Middle East, but has generated heated speculation in that regard.

The Arctic Sea is a Malta-flagged vessel that departed Finland on July 21 with more than a dozen Russian crew members and a cargo of timber worth about $1.8 million. A few days after departure, a group of men boarded the ship. It was first reported that they claimed to be environmentalists seeking shelter from a storm, but by the time they boarded the ship, they were wearing clothes and masks that identified them as police.

The vessel continued to send signals suggesting that all was normal for a week; on July 30 radio traffic ceased and the vessel disappeared. That triggered a massive hunt until the vessel was found Aug. 16, off the coast of Cape Verde, a considerable distance from its intended destination of Algeria, and eight alleged hijackers on board were arrested.

That short story raises a lot of questions. First, the idea of a pirate attack in the Baltic Sea, some of the world's most traveled waters, is far-fetched. Second, why would pirates target a ship with a relatively low-value cargo? Moreover, why the silence and the changing of stories after the supposed attack?

The mystery thickened the day after Russian announced it had found the ship, and Mr. Peres made a surprise visit to Russian President Dmitry Medvedev. The speculation became even more feverish on Sept. 7, when Mr. Netanyahu also "vanished" for a day. Officially, the Israeli prime minister was visiting "a security facility." Slowly, however, news leaked out that Mr. Netanyahu had boarded a private jet for his own secret visit to Russia. The Israeli government continues to stonewall inquires about the prime minister's whereabouts, but winks and nods to the press suggest that speculation is correct.

In Moscow, he reportedly voiced concern over the possible sale of Russian anti-aircraft missiles to Iran. That provided substance to earlier suggestions that Mr. Peres had also pressed the Russian president to reconsider the proposed sale.

Those reports shine some light on the Arctic Sea's voyage. Before it set out with the lumber, it spent two weeks undergoing repairs in the Russian port of Kaliningrad. Maritime experts believe that the ship picked up another cargo at that stop, one that wasn't on the reported manifest.

By this logic, it was that cargo that the hijackers were interested in. By seizing the ship they intercepted a planned delivery of weapons, perhaps missiles, intended for the Middle East, most likely Syria or Iran.

The crew might be able to answer some of the questions about this episode, but they have been told to make no comment since they returned to Russia. And, intriguingly, the Russian expert who first suggested the Arctic Sea was carrying a secret cargo has been threatened and forced to flee the country.

The entire incident casts some light — however unfocused — on the volatile situation in the Middle East and the role that external powers play in keeping that conflict alive. There is a lively trade in weapons that fuels the violence. Israel has been increasingly vocal in its complaints about Iran and the threats it sees from Tehran's support of Islamic extremists as well as its alleged pursuit of a nuclear weapon, an intention that Iran denies it has. Not surprisingly, Israel is worried about the acquisition by Iran of more advanced antiaircraft missiles, which would ostensibly be deployed to protect nuclear facilities.

In another twist in an already twisted tale, some observers believe that Russia may have dispatched the hijackers to grab the illicit cargo. That means that Moscow may not be aware of — or control — all the activities of its vaunted weapons industries. But if Russia was aware of the shipment, and the Israel secret services were responsible for the heist, then the Israeli officials' visits were a warning to Moscow.

One way or another, Russia plays a crucial role in the Middle East. In addition to providing weapons, it has sold a nuclear reactor to Iran, and Moscow has a veto in the U.N. Security Council. Close ties with Tehran give Russia considerable influence. As Iran ups the ante on discussions of its nuclear program, Moscow's thinking matters: At a minimum, no deal is likely without its approval. Moscow's skepticism about the utility of sanctions against Tehran blunts that tool.

Unfortunately, there is little indication of how Russia can contribute to a solution in the Iranian situation.