On Tuesday, Special Prosecutor Robert Mueller made another surprise indictment, this time of a London-based lawyer for allegedly lying to the FBI.

Like two of Mueller’s previous targets, Paul Manafort and his deputy Rick Gates, the lawyer—a man named Alex Van Der Zwaan—had done work for Ukraine’s previous, pro-Russia government, which was overthrown in a popular uprising in 2014.

And according to the indictment, the false statements in question were about communications he had in 2016 with Rick Gates and an unnamed “Person A” related to that work.

So on its surface, Tuesday’s indictment relates solely to a single branch of Mueller’s investigation: Paul Manafort’s dealings with the pro-Russia faction in Ukraine.

But search beyond the scant details offered in the two-page indictment and there’s an intriguing link to a whole other branch of Trump-Russia inquiry: the Alfa Bank mystery.

As it so happens, Van Der Zwaan, the lawyer indicted Tuesday, is the son-in-law of Russian oligarch German Khan. Khan is a director and co-owner of Alfa Bank and one of three key leaders of its parent company, the sprawling conglomerate Alfa Group.

Those of you following along at home will remember Russia’s Alfa Bank popped up prominently in the Steele Dossier—and figured in news reports that the FBI was investigating unexplained connections between the Trump Organization and computer servers owned by the bank.

The exact nature of the relationship—if there is one—between Alfa Bank and Trump World, has been unclear. But with Van Der Zwaan, who pleaded guilty on Tuesday, Mueller may have quietly given us a new connection worth noting.

Here’s what we know:

Van Der Zwaan’s father-in-law, Khan, is named in former British spy Christopher Steele’s dossier in a section that deals exclusively with Alfa Bank and its relationship to Putin. In the dossier, Steele alleges that the bank and its founders remain close to the Russian president and that they continued to trade “significant favours” between them.

The bank and its executives have denied the allegations in the Steele Dossier. And last May, Khan—along with two other Alfa Bank co-founders, Mikhail Fridman and Petr Aven—brought a defamation suit against BuzzFeed and several of its journalists after they published those portions of the dossier.

While the dossier didn’t posit any relationship between Alfa Bank and Trump, much has been made of the mysterious communication between one of the bank’s computer servers and a server owned by the Trump Organization. The communication occurred at a time, during the campaign, when very few other serves in the world were trying to communicate with the Trump server. (Most of the other attempts to communicate with the Trump server during that period apparently came from a Michigan company owned by the family of Trump’s future education secretary, Betsy DeVos, the sister of international-man-of-intrigue Erik Prince.)

Tech experts remain befuddled by the links between the Trump server and that of Alfa bank, and both companies have said the servers were not part of any communication backchannel and have suggested instead that the activity could be explained by spam marketing emails. But federal counterintelligence investigators have reportedly taken an interest in the activity, and the Trump Organization and Alfa Bank have never quite landed on the same page about the matter,

As of last March, CNN reported that the FBI was still scrutinizing the servers and that the “companies involved have provided CNN with new explanations that at times conflict with each other and still don't fully explain what happened.”

It’s all a lot to wrap one’s head around. In the small world of the new Russian elite, the fact of Van Der Zwaan’s family ties to Alfa could be coincidental. And the indictment bears no discernible relationship to the bank.

But in the fog surrounding the Mueller investigation, this latest indictment provides one more reason to keep an eye on Alfa Bank.

Ben Schreckinger is a GQ correspondent in Washington, D.C.