President Donald Trump walks towards Marine One to depart for Cincinnati on the South Lawn of the White House in Washington, D.C., U.S., on Wednesday, June 7, 2017. Eric Thayer | Bloomberg | Getty Images

I. Setting the stage

July 2016: The Russia investigation begins. In late July 2016, the FBI opens an investigation into the hacking of the Democratic National Committee's emails. In the ensuing months, government officials will attribute this and other political hackings to the Russian government. This investigation turns toward examining broad Russian interference in the US election process, links of Trump associates and the Trump campaign to the Russian government, and whether there was any coordination between Russia and the Trump campaign. In the ensuing months, other agencies — including the CIA, the NSA, and the Treasury Department's financial crimes unit — get involved. They scrutinize financial transactions and intercept Russian communications, per the New York Times. January 6, 2017: Trump and Comey first meet during the transition to talk Russian hacking and supposed "kompromat." The context for this meeting is that Trump had repeatedly professed, both before the election and then during the transition, that he was skeptical that Russia was behind the hackings. So on January 6, FBI Director James Comey and other top intelligence officials meet with President-elect Trump to present him the evidence on Russian culpability. According to Comey's later testimony, at the end of the briefing, he is tasked by other officials with pulling the president-elect aside to tell him about a salacious and unverified dossier claiming Russia had collected compromising information about him. (This dossier, assembled by former British spy Christopher Steele, is posted online by BuzzFeed Newsfour days later, and at least some of its claims seem very dubious.) Comey's testimony also says that at this meeting, with the prior approval of FBI leadership, he offers the "assurance" to Trump that he isn't being investigated personally. He says this "was true; we did not have an open counterintelligence case on him." Immediately afterward, he says, he documents what happened in the meeting in a memo. Sometime shortly before the inauguration: Trump asks Comey to stay on. According to Comey's testimony, Trump calls him shortly before becoming president to reaffirm his rejection of the allegations in the dossier, and tells him, "Hope you're going to stay, you're doing a great job." On January 18, Comey tells senior FBI employees in a conference call that Trump has asked him to stay in his post, according to the New York Times, quoting "people briefed on the matter." The story also says that according to those people, Trump's aides "have made it clear" to Comey "that the president does not plan to ask him to leave." January 22, 2017: Two days after Trump is sworn in, he has a brief, awkward encounter with Comey at a public event. The new president holds a reception for law enforcement leaders at the White House. Comey is invited, and Trump signaled him to come over for what proves to be an awkward part hug, part handshake. "He's become more famous than me," Trump says. Comey testified that during the handshake, Trump whispered in his ear, "I really look forward to working with you." Comey will later tell a friend he felt very uncomfortable during this encounter. January 27, 2017: One week after Trump became president, he has Comey over for a private dinner, and reportedly asks for his "loyalty." Comey's testimony describes this unusual dinner, which he says he documented in a memo immediately afterward, at length. Comey says Trump invited him earlier that day, but that he didn't expect it would be just the two of them there.

Trump began the dinner by asking him whether he wanted to stay on as FBI director, which Comey says he found strange considering he thought Trump had already asked him twice to stay on. Comey says he suspects Trump wanted to create "some sort of patronage relationship" with him, and that he responded by saying he was not "reliable" in the political sense but that he'd always tell the truth.

Per Comey, Trump responded, "I need loyalty, I expect loyalty," while he himself tried to remain stone-faced.

Later in the dinner, Comey says, Trump again told him, "I need loyalty." Comey says he offered "honesty," that Trump responded by saying he wanted "honest loyalty," and that he himself then agreed, "You will get that from me." Comey says it was "a very awkward conversation."

Additionally, Comey says Trump again brought up sexual material in the Steele dossier, denied that it was true, and suggested he might order the FBI to investigate it to prove its falsehood. Comey says he cautioned Trump by saying that "might create a narrative that we were investigating him personally, which we weren't" — his second assurance to Trump that he wasn't under investigation. President Trump's account of the dinner, given in an interview with NBC's Lester Holt in May, claims instead that it was not him but Comey who asked to have dinner "because he wanted to stay on." The president and his personal attorney have also flat-out denied that Trump ever asked Comey for loyalty. "I will tell you that I didn't say that," Trump said at a June 9 press conference. "The President also never told Mr. Comey, 'I need loyalty, I expect loyalty' in form or substance," Trump's attorney Marc Kasowitz said in a statement that same week.

II. From Michael Flynn's firing to Jeff Sessions's recusal

III. Comey goes public with the investigation — and President Trump isn't happy

IV. Comey's firing and the aftermath

V. What's happened since Mueller's appointment