Welcome to The Investigation. I'm Chris Vlasto, Senior Executive Producer here at ABC News,

and I'm joined here by my colleagues John Santucci, who's one of the lead reporters covering

the Trump investigation, along with his colleague, Catherine Foulders, who's concentrating on

Congress and the White House,

as a reporter on this story. There were a lot of developments this weekend in the impeachment inquiry,

especially one big exclusive that appeared on the Sunday show this week with George Stephanopoulos.

ABC News has learned that the legal team representing the first whistleblower is now representing a second whistleblower.

Attorney Mark Zaid told me that this second whistleblower is a member of the intelligence

community with firsthand information on some of the allegations at issue.

And the reporter behind the scenes who helped break that story is a member of our team, James Gordon Meek,

and he is a specialist in national security issues. James,

tell us about the story and what is the significance that there is a second whistleblower.

So we knew that there were probably more than six or seven because the whistle, the first whistleblower

and his complaint to the intelligence community's inspector general,

the internal watchdog for all the intelligence agencies in the United States, had said that there

were more than half a dozen officials who had expressed concerns about the president's dealings with

Ukraine and his phone call with the Ukrainian president. So we were told

early on that the inspector general is part of his initial 14-day preliminary review of the

allegations had interviewed multiple witnesses. So that would be presumably the whistleblower,

the first one, and other people who had expressed concern to the first whistleblower, if that's

not too confusing.

But now we have a second whistleblower.

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