The Panama Papers trove is by sheer volume of documents, the largest whistleblower leak in history.

With more than 100 news organizations for more than 80 countries involved,

it's also the largest journalistic collaboration ever.

And it has already claimed its first scalp.

The Icelandic Prime Minister, Mr. Gunlaugsen, has now stood down.

He's accused of hiding millions of dollars in investments behind a secretive offshore company.

The context to all of this is the financial crash in 2008.

Some of the failed banks here were using shell companies in offshore havens, and what

happened nearly brought down this economy. But the 11.5 million documents from the Panama law firm

Mosac Fonseca also exposed shadowy dealings surrounding dictators and kleptocrats worldwide. Most notably so far, Robert

Mugabe of Zimbabwe, Bashar al-Assad of Syria, and Vladimir Putin, with 99% of the iceberg

still submerged. The material has been scrutinized by some 400 reporters for the past year

under the coordination of the International Consortium of Investigative Journalists.

Gerard Ryle is the consortium director.

Gerard, welcome back to O.T.M.

Thank you for having me.

This massive story began with a single encrypted chat message sent a year ago to Bastien Obermeier

at the German newspaper Su Deutsche Saitong. It said, quote, hello, this is John Doe, interested in data,

and thus commenced a very complex endeavor. What happened next? Well, Bastion picked up the phone and he rang me,

and once he'd realized that the names he was looking at went to several different countries,

and he proposed that we really should do this as an international collaboration. A few days later,

I found myself on a plane to Munich. We spent about

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