The 2012-issued passport of President Donald Trump's former campaign chairman was admitted into evidence during Manafort's 2018 trial.Reuters / Department of Justice

In the Collected Works of Robert Mueller, there are Russian names that come and go. But there’s only one of these figures who provides a recurring presence in this oeuvre. He is a diminutive man, whom Mueller has called an “asset” of Russian intelligence. His presence is either the sort of distracting irrelevance that Alfred Hitchcock described as a MacGuffin, or he is the shadowy character who steps into the frame to foreshadow an ominous return.

Konstantin Kilimnik trained in Russian military intelligence as a linguist; he spent decades by Paul Manafort’s side, serving as a translator and then rising through the ranks of his organization. Eventually, Manafort would come to describe Kilimnik—also known as K.K. or Kostya—as “My Russian Brain.” He would travel with Manafort to Moscow to meet with their client, the Russian oligarch Oleg Deripaska. When Kostya worked with Americans, they suspected him as some sort of spook. (Last June, I wrote this profile of him.)

When Paul Manafort cut a deal with Mueller in September, he promised to come clean. Any student of Manafort knows that coming clean is not a skill that comes naturally to the man. He built a career around his expertise at distorting images of scuzzy public figures; he made a fortune by erecting fantastically complicated financial contraptions that hid his money from governments, so ridiculously intricate that it is a miracle they worked in the first place. These habits of misdirection, this engrained proclivity toward the construction of expedient narratives, can’t be easily shed.

Everything we know about Paul Manafort also suggests that he would never stop working the angles. If there was a prospect of a presidential pardon, no matter how distant, he would make a play for one. Still, I don’t think this sort of legal gamesmanship fully explains why Paul Manafort would have continued to lie to Robert Mueller, when he obviously knew the risks of misleading the Special Counsel’s Office—and when Manafort had ample personal evidence of Trump’s flakiness and indifference to the fate of loyal servants.

Of course, it’s hard to see exactly where Mueller intends to take his investigation; we must take into account the redactions in his filings and his necessary silence about matters he continues to investigate. But I think there’s a reason that he seems to care so much about Kilimnik—and Manafort’s alleged lies about him.

To recap some of the crucial plot points in the Paul Manafort story, based on my own reporting and lawsuits filed against him:

1. He owed millions of dollars to Oleg Deripaska, who invested in a fund that Manafort created for buying up assets in Russia and Ukraine.

2. Manafort was so deep in debt to Deripaska that he avoided him when the oligarch came asking for his cash in 2010.

3. When Manafort went to work for the Trump campaign, he suggested giving Deripaska “private briefings,” with the hopes of the Russian forgiving his debts. (All this is obliquely explained in emails obtained by The Atlantic last year.)

Perhaps Manafort’s messages about campaign access never reached Deripaska; it’s possible that this was another one of his harebrained schemes. But we know that Manafort was attempting to use Kilimnik as his interface with Deripaska.

As I have read back over Mueller’s past references to K.K. in his sundry filings, there’s one mention that stands out. Last March, almost as an aside, Mueller noted that Kilimnik “has ties to a Russian intelligence service and had such ties in 2016.” Manafort would have recognized this instantly as a description of K.K., and yet he repeatedly misled the prosecutor about his relationship with him, according to Mueller.

One reason that Manafort might have lied about his contacts with K.K. could be that he doesn’t want to be vulnerable to charges greater than the ones that Mueller has already leveled against him. It’s one thing to admit to a failure to adhere to the Foreign Agents Registration Act; it’s quite another to implicate yourself in an effort to collude with a hostile regime, to admit that your closest aide is a Russian spy.

There’s been talk that Robert Mueller has reached the point in his investigation where he’s tying together loose threads. But reading through both of the special counsel’s filings yesterday, it’s striking how many threads there are. And even as we get greater evidence of contact between Trump aides and Russians, there’s still so much that remains vague or maddeningly elliptical. The bigger picture fills in, pixel by pixel, but we still don’t quite know what we’re seeing yet.

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