The Clinton Plan.
Try to think of it like a simple logical diagram.
James Comey, among others, are briefed of a possible plan hatched by the HRC team to link Trump to Russia to help distract from HRC's email scandal, and obviously by extension harm Trump.
Soon after the FBI is receiving more and more information from Steele, who had been hired by Fusion who was hired by the HRC campaign.
At a minimum Comey and Strzok knew of Step 1 and obviously they and many more knew of Step 2.
The FBI begins seeing things that they are being given turn up in newspaper reports which initially damages their relationship with Steele.
Now, think of all involved and what they knew. The CIA obviously was aware because it was Brennan who briefed the others. The others (Comey, Obama, Lynch,...) knew because they had been briefed. Obviously all of these people were aware of what was being reported at the time.
Knowing of the possible "Clinton Plan", and then all of this stuff being passed around Washington, is it not reasonable to infer that at least one of these seemingly intelligent people might have said "gee ya know guys, kinda weird how we heard about that Clinton plan and now all this stuff is being passed around Washington."