Welcome to the beat I'm Ari Melber.

And while we try to do it all with a good spirit,

as I just mentioned to my colleague,

there is a lot going on.

We will deal in the facts and the precise aspects

of what we know because we don't know everything

and we don't know the future.

But here's some of what we do know

that I'm gonna bring you in what I can tell you

will be a pretty packed broadcast tonight.

Donald Trump's number one aid during the insurrection

and the classified documents hand over,

Chief of Staff Mark Meadows,

just went under oath recently in this pro.

That news just broke yesterday.

We don't have the exact date that we went under oath,

but he is someone you'd get to more towards the end

than the beginning.

He's a key witness.

And his lawyer is now saying he is completely committed

to telling the truth, the language of someone

cooperating with a special counsel probe

...