Expect the questions to range even wider than that, though. Cohen spent over a decade working for Trump, and he has insight into the Trump Organization’s inner workings that few can match. (Relatedly, remember that Trump Organization CFO Allen Weisselberg has been cooperating with investigators since August.)

Cohen's prepared testimony, released ahead of the hearing and embedded directly below, claims not only that Trump is racist and duplicitous, but that the president was aware of the alleged conversations between adviser Roger Stone and WikiLeaks. Cohen apparently lacks any corroborating, documentary evidence to back up this claim. But he does purport to have financial documents, letters, and a copy of a check that all point to a variety of apparent malfeasance, including the notorious payment to silence porn star Stormy Daniels. Trump has denied involvement.

Which is not to say that the hearing will be a calm recitation of alleged facts. The White House has already sought vigorously to discredit Cohen; press secretary Sarah Sanders said in a statement that “it’s laughable that anyone would take a convicted liar like Cohen at his word, and pathetic to see him given yet another opportunity to spread his lies.” Florida representative Matt Gaetz, a vocal Trump supporter, struck an even more aggressive note, suggesting in a since-deleted tweet that he would give compromising information to Cohen's wife and father-in-law about alleged infidelities on the eve of Cohen's testimony.

Gaetz quickly rebuked the notion that the tweet amounted to witness tampering, telling The Daily Beast that he was “challenging the veracity and character of a witness” and competing “in the marketplace of ideas.” Gaetz is not on the House Oversight Committee, so he won’t be questioning Cohen. But fellow Trump defender Jim Jordan is its ranking member.

This is just the latest stop on Cohen's long road of trials and testimonies. In December, Cohen was sentenced to 36 months in prison on a wide array of charges; he will begin serving his time in May. On Tuesday, he was officially disbarred in the state of New York.

Join us Wednesday to see what unfolds! And if you need a quick primer on what the big deal is about this Cohen guy in the first place, you might want to start with his 10-page guilty plea, below.

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