John Daniel

Thanks to Steve Burridge, Ali Marsden, Jeremy Ansell and William Saunders.

Thanks to Megan Whelan and thanks also to Susan Baldacci.

Thanks also to CNN, TVNZ, BBC, the ABC, Universal and Paramount.

To read more about the documents and articles we've mentioned, you can go to rnz.co.nz forward slash the agency and you can see the links in the show notes.

Previously on the agency.

Aldrich Ames, or Rick Ames, had worked for CIA in various guises since the early 1960s.

He'd risen to a lead role in the Southeast Asia Division of the Soviet and East European section when he began passing secrets to the KGB in 1985.

But this wasn't discovered until 1994.

Yeah, it's hard to be sure exactly what happened with Vladimir and the operation against the GRU.

Aldrich Ames began his betrayal in 1985, but it went on for nine years.

It was probably the worst penetration of the CIA in its entire history, and the wider understanding of what happened would take decades to piece together.

This is a clip from ABC's Nightline in 2014.

Yeah, although Ames is only able to throw Gordievsky under the bus because of some pretty bad behaviour from CIA themselves.

They shouldn't have known Gordievsky's name.

Very few people at MI6 knew his name.

It was highly secret for exactly this reason.

You've got to keep maximum security for the safety of the person who has entrusted you with their life.

MI6 had shared the information they were getting from him with CIA and probably other Five Eyes partners, but Gordievsky himself was known only by a codename to them.

Yes, it has.

So CIA analysts pull together all the information they have from this source, and by cross-checking with what they know from their side, they end up being able to put a real identity to the codename.