The special counsel probe is nothing if not … colorful. Today’s featured player on the Russiagate stage comes direct from another scandal entirely. Kristin Davis, the former “Manhattan Madam” who supplied then-governor Eliot Spitzer with prostitutes, emerged from prison in May 2016 and had nothing to do with the Trump campaign. So why is she talking with the grand jury? Most likely to talk about Roger Stone, although he never worked directly on Donald Trump’s campaign either:

Davis, 41, who said she had supplied prostitutes to then-New York Gov. Eliot Spitzer, was subpoenaed by Mueller last month as part of his probe into Russian meddling in the 2016 U.S. presidential election. Davis had said through her lawyer that she was cooperating with the special counsel, while noting that “I don’t have anything” to offer regarding “information on Russian collusion.”

She also met last week with members of Mueller’s team. Stone told CNBC last Friday that “She knows nothing about alleged Russian Collusion, WikiLeaks collaboration or any other impropriety related to the 2016 election which I thought was the subject of this probe.”

Stone has become a major focus of Mueller’s investigation, CNBC has reported. Beyond his connections to Wikileaks founder Julian Assange, whose website published emails allegedly stolen from Democrats by Russian sources, Mueller is looking at Stone’s interactions with ex-Trump campaign official Rick Gates, sources told CNBC.

We’ll get back to Gates in a moment. Stone, himself a colorful player on the political stage, did serve as an informal advisor to Trump and did a lot of media as a surrogate during the campaign. He ran a Trump-supporting PAC, which at one point threatened “Days of Rage” if Trump didn’t win the nomination. That drew a rebuke from then-RNC chair Reince Priebus, who called the threat “totally over the line,” at which point Stone backpedaled, claiming all he meant was a “discussion.”

So it’s been colorful, but most of Stone’s work took place before Kristin Davis got out of prison. After that, Stone told CNN, Davis’ connection to him was mostly centered on “help[ing] me build some websites.” Mueller’s team isn’t buying that, obviously, but what do they think she can provide? Maybe it doesn’t have anything to do with Trump — at least not directly:

Davis’ appearance is shrouded in mystery and it remains unclear what Mueller’s interest in her may be. But she is close with Roger Stone, a longtime political adviser to President Donald Trump and one of his brashest defenders. Davis worked closely with Stone for years during her fleeting forays into New York politics — she ran for governor in 2010 — and is even the godfather to her young son. …

It could also be the latest sign that prosecutors are tightening a ring around Stone, whom Democrats say has not been forthcoming about his 2016 contacts with WikiLeaks and its founder Julian Assange; the website released thousands of Democratic emails during the last presidential campaign that proved highly damaging to Hillary Clinton. …

Stone is clearly under Mueller’s spotlight. The special counsel’s team of prosecutors have already interviewed longtime Stone colleagues Sam Nunberg and Michael Caputo. Another Stone aide, Andrew Miller, is fighting a Mueller subpoena in court. And on Thursday, MSNBC reported that Mueller’s team is prepared to issue another subpoena to Stone associate Randy Credico, a comedian and former talk radio host who Stone has said was in touch with Assange.

Stone has previously said he is prepared to be indicted, though he insists that if he is, it would be for an “extraneous” business-related infraction unrelated to Russian election meddling.

If Mueller’s interested in work Stone did with Gates, that would make some sense. Mueller’s stuck with the Manafort trials now, apparently not getting anything useful out of Trump’s former campaign manager. Anything Gates has to provide on other cases would go through Mueller first. However, the case on Gates and Manafort is almost entirely comprised of charges that long predate the Trump campaign, with the exception of lying to investigators. How would Stone figure into that? If Stone took part in those crimes, wouldn’t Mueller have indicted him along with Manafort, especially with Gates’ testimony available?

It seems more likely that Mueller’s using Davis to gain leverage on Stone. Having failed to flip Manafort, the special counsel needs someone in the Russia-campaign nexus to spill the beans, and Stone’s the next likeliest candidate. He’s admitted to private communications with Guccifer 2.0, now believed to be a Russian-intel front, and Wikileaks in exploiting the hack of the DNC and John Podesta. However, Stone pointed out that the Guccifer 2.0 contact was after the leak, and argues that the Wikileaks contacts were innocuous.

Stone thinks he’s being squeezed, too. Note the dig at CNN for hiring Spitzer while Davis “went to prison”:

After noting Mueller’s apparent strategy of “squeezing underlings to get them to compose testimony against a bigger fish,” Stone told CNN’s Anderson Cooper Wednesday. “I would not rule out cooperating if I could be helpful in some area.”

It seems pretty late in the game for Mueller to be using a squeeze play this indirect to go after a loosely connected figure like Stone. Clearly Mueller’s team sees some value in Davis’ testimony, or they wouldn’t have brought her to the grand jury at all. It doesn’t have much direct value on the question of collusion with Russia, however, unless the grand conspiracy was run out of the federal prison where she was serving a two-year sentence for selling drugs to an undercover FBI cooperator.