Special counsel Robert Mueller dropped a heavily anticipated sentencing memo on Tuesday for Michael Flynn, who pleaded guilty to making false statements to the FBI about a year ago. You’ll quickly notice that the memo has large sections that were redacted — because they describe Flynn’s assistance with investigations that are still ongoing.

But there’s a lot in the text itself and between the redacted lines in the documents, amounting to four key takeaways.

First off, Mueller is quite happy with Flynn’s cooperation — happy enough to recommend that he serve no prison time. (This is a notable contrast to the positively scathing memo Mueller’s team wrote about George Papadopoulos, in which they said he did not provide “substantial assistance” and complained that he talked to the press.)

Second, Flynn is cooperating in not one but three different investigations — Mueller’s investigation of the Trump campaign’s ties to Russia, a separate criminal probe, and a third investigation of some kind. But most of the details of these other probes are redacted, including even the type of the third investigation.

Third, the cooperation Flynn provided to Mueller’s probe specifically appears to break down into two main areas. One focused on contacts between the Trump transition team and Russia, but we don’t know what the other one is yet.

Finally, the many redactions indicate that there’s still a whole lot going on behind the scenes that Mueller doesn’t yet want the public to know about.

Mueller is very happy with Flynn’s cooperation

The special counsel praises Flynn’s assistance as “substantial,” writing that a “sentence that does not impose a term of incarceration” for him would be “appropriate and warranted.”

“His early cooperation was particularly valuable,” Mueller writes, “because he was one of the few people with long-term and firsthand insight regarding events and issues under investigation by the SCO” (special counsel’s office).

Mueller adds that Flynn’s decision to cooperate “likely affected the decisions of related firsthand witnesses to be forthcoming with the SCO and cooperate”— and redacts the sentence that follows.

As for the specifics of Flynn’s assistance, Mueller writes that he has “participated in 19 interviews” with either the special counsel’s office or attorneys from other Justice Department offices, as well as providing “documents and communications.”

Flynn seems to be cooperating with three investigations

The special counsel appears to write in a partially redacted passage that there are three investigations Flynn is helping with.

So, those three are:

  1. A criminal investigation, the topic of which is redacted
  2. The Mueller investigation into links between Russia and the Trump campaign
  3. Another redacted investigation (even the type of this one is redacted)

For that first investigation, the criminal one, Mueller writes that Flynn has “provided substantial assistance,” but then entirely redacts the three-paragraph long section explaining how.

That third investigation appears to be described in one brief paragraph near the end of the memo, but it is fully redacted.

How Flynn helped the Mueller probe

The middle of the document focuses on how Flynn helped Mueller’s own investigation into Trump associates’ Russia ties. This is largely redacted as well — but not entirely.

Mueller says Flynn helped his investigation “on a range of issues, including interactions between individuals in the Presidential Transition Team and Russia.” Then he mentions something else that is redacted. So there appear to be two main areas here where Flynn is helping.

The first section focuses on those transition team interactions with Russia. Mueller starts with the conduct to which Flynn pleaded guilty — his own interactions with Russian ambassador Sergey Kislyak in December 2016, about a United Nations Security Council vote and about sanctions.

The memo also mentions that other transition team members “publicly repeated false information conveyed to them” by Flynn about his contacts with Kislyak. This appears to refer to at least two people: Sean Spicer and then-vice president-elect Mike Pence, who said publicly at the time that Flynn and Kislyak had not discussed sanctions.

That section on the transition contacts ends with a few more redacted lines. We of course don’t know what they say, but one obvious question has long been just what Donald Trump knew about Flynn’s contacts with Kislyak, and the false information Flynn gave to Pence and Spicer. This would something Flynn could clearly explain to the special counsel.

A second section appears to follow, signifying a topic change, but it’s redacted. Mueller writes that Flynn “also provided useful information concerning” … well, something, but the following two paragraphs are then redacted.

There’s a lot Mueller still isn’t ready to tell us

Amid a new round of reports and rumors that Mueller is preparing to wrap up his investigation, the Flynn sentencing memo makes clear that the special counsel isn’t ready to show all his cards just yet.

Not only are significant sections of the Trump-Russia section of this memo redacted, but sections on two other separate investigations are entirely redacted. It’s a reminder of how little we know about what’s going on behind the scenes at the Justice Department — and how much, it seems, remains unresolved.